Monazite recorded Paleoproterozoic granulite-facies metamorphism and Triassic fluid modification of the Weihai pelitic granulite,Sulu orogen

作     者：Zhiwu XIONG Haijin XU Pan WANG Junfeng ZHANG Zhiwu XIONG;Haijin XU;Pan WANG;Junfeng ZHANG

作者机构：School of Earth SciencesChina University of GeosciencesWuhan430074China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2021年第64卷第6期

页      面：932-950页

核心收录：

学科分类：070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 070901[理学-矿物学、岩石学、矿床学] 0708[理学-地球物理学] 0704[理学-天文学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42072058 41772054 41572039) 

主　　题：Pelitic granulite Monazite Paleoproterozoic Triassic Sulu orogen 

摘      要：Monazite is an important accessory mineral in the pelitic granulites(Weihai area,Sulu orogen),and is also a powerful monitor for understanding the metamorphic evolution of the *** pelitic granulites incongruously occur as lenses in granitic *** lithologies of the lenses gradually change from core to margin:The undeformed coarse-grained granulite,the foliated fine-grained granulite,the garnet-biotite-gneiss,and the migmatized *** lens cores mostly preserve a peak granulite-facies metamorphic mineral assemblage of garnet+plagioclase(antiperthite)+quartz+sillimanite+biotite with accessory minerals of rutile,zircon,and *** lens margins display a fluid-induced *** order to decipher the metamorphic processes of the pelitic granulites,a combined study of BSE imaging,U-Pb dating,and trace element composition for the monazites from the metapelitic lens were *** from the undeformed coarse-grained granulite only record a Paleoproterozoic age(1832±7 Ma,n=40).Monazites from the other lithologies yield the inherited Paleoproterozoic age and Triassic overgrowth *** example,monazites from the migmatite yield intercept ages of 1818±10 and 211±22 Ma(n=56)with Triassic concordant age of 223.8±2.9 *** Paleoproterozoic monazites are characterized by remarkable depletion in HREE and Y with obviously negative Eu anomalies,indicating their formation equilibrated with garnet and feldspar under granulite-facies *** Triassic fluid modification,the monazite bright rims assimilated Th and Si but released U,HREE,Y,and *** process resulted in that the Triassic overgrowth monazites have higher HREE and Y contents,and lower Th and U contents with relatively low Th/U ***,the monazites in the pelitic granulites recorded a Paleoproterozoic metamorphic event and Triassic fluid *** Weihai pelitic granulites might have a tectonic affinity with the North China ***,the Paleoproteroz