Application of Detrital Apatite U-Pb Geochronology and Trace Elements for Provenance Analysis,Insights from a Study on the Yarlung River Sand  

作　　者：Yufeng Du Guangwei Li Danyang Liu Xianyan Wang Dongxu Cai Xiaolu Dong Qi Yu 

机构地区：[1]State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing,210023,China [2]School of Geography and Ocean,Nanjing University,Nanjing,210023,China

出　　处：《Journal of Earth Science》2024年第4期1118-1129,共12页地球科学学刊（英文版）

基　　金：supported financially by the National Natural Science Foundation of China(No.42272111);the Second Tibetan Plateau Scientific Expedition Program(Nos.2019QZKK0204,2019QZKK0205).

摘　　要：Detrital U-bearing minerals(e.g.,zircon,apatite)U-Pb ages with specific trace-element geochemistry,are frequently used in provenance analyses.In this study,we focus on the Yarlung River drainage in South Tibet,characterized by two distinct lithologic units:The Gangdese batholith to the north(mainly granitoids)and the Tethyan Himalaya(mainly sedimentary rocks)to the south,which plays a crucial role in the erosion of the Tibetan Plateau.To constrain the provenance of the Yarlung River Basin,we performed trace-element and U-Pb age analyses of detrital apatite from the river sands of the Yarlung River and its tributaries.Our findings indicate that the detrital apatite U-Pb age patterns of the north tributaries exhibit main peaks at approximately 40 and 60 Ma,consistent with the corresponding U-Pb age patterns of detrital zircon published.Further,their trace element casts fall mainly in the Type I granite region,also indicating the Gangdese arc-dominated source.However,those of the south tributaries(∼60–20 Ma)exhibit a different age distribution from the detrital zircon U-Pb groups(∼110–150,∼500,and 1100 Ma),suggesting that the detailed apatite U-Pb signals can provide excellent constraints on the provenance of igneous and metamorphic rock sources but less so for sedimentary rock sources.Combined with previous detrital zircon data in the study area,our detrital apatite information can highlight young metamorphic events from a complex background(i.e.,Niyang and Nianchu rivers),which offers additional constraints on the provenance of the Yarlung River Basin.Generally,a combination of geochemistry and geochronology of multi-detrital heavy minerals,such as zircon and apatite,can provide powerful tools for provenance analysis.

关 键 词：APATITE detrital apatite U-Pb age trace elements provenance analysis Yarlung River Tibetan Plateau GEOCHRONOLOGY 

分 类 号：P595[天文地球—地球化学]