Here we present zircon U-Pb-Hf and whole-rock major and trace element studies of eastern Ningzhen W-Mo-ore-related magmatic rocks,Yushan and Long-wangshan granitic rocks,to constrain their form timing,magma sources,and tectonic settings.The results showed that the two plutons were formed in the Early Cretaceous with 206Pb/238U ages of 107.8±1.2 and 105.2±1.5 Ma(206Pb/238U),respectively.The trapped/residual zircons are mainly distributed in 2.0-2.5 Ga.The two intrusions are characterized by high silicon(68.60-73.99％),high alu-minum(13.56-15.02％),high Mg#(47-55),high Sr,Sr/Y,LaN/YN,and low Yb,falling into high Mg#adakitic rock region.The zircon eHf(t)values of the two intrusions range from-24.8 to-13.2,indicating an ancient conti-nental crust in their magma sources.The average Ti-in-zircon temperature is 689℃,slightly higher than those of other high-Mg adakitic rocks in the lower Yangtze River belt,but lower than those of high-Mg adakitic rocks in the Southern Tanlu Fault(STLF).Zircon Ce4+/Ce3+show low oxygen fugacity(LWS-1:3-400,average 92;sample ZYS-4:9-382,average 93).These geochemical features indicate a thickened lower continental crust in the Eastern Ningzhen region in a subduction setting.Comparing the geochemical characteristics of the eastern Ningzhen to the western Ningzhen and other areas in the Lower Yangtze River Metallogenic Belt(LYRMB)and the high-Mg ore-barren adakitic rocks of the STLF,we propose that the magmatic rocks from eastern Ningzhen may be mainly from a thickened lower continental crust that hybridized with a very small part of mantle sources,while the west Ningzhen magmatic rocks may have experienced a higher degree of mantle contaminations in their source.The metallogenic differences between the eastern(W-Mo)and western(Cu-Fe-Pb-Zn)parts of Ningzhen also indicate different pro-portions of crustal materials in their magma source.

Fangyue Wang;Yongjie Guo;Haiyang Yan;Haiou Gu;He Sun;Can Ge

School of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,China;Ore Deposit and Exploration Center,Hefei University of Technology,Hefei 230009,China;Anhui Institute of Geological Survey(Anhui Institute of Geological Sciences),Hefei 230001,China

地球化学学报（英文版）

[1]Fangyue Wang;Yongjie Guo;Haiyang Yan;Haiou Gu;He Sun;Can Ge-.Geochronology and geochemistry of the W-Mo-ore-related granitic rocks from eastern Ningzhen,lower Yangtze river belt,eastern China)[J].地球化学学报（英文版）,2022(02):288-306

Ningzhen,Yushan,wangshan,Mg#adakitic,Ce3+show,LWS,ZYS,LYRMB

Geochronology,geochemistry,Mo,ore,related,granitic,rocks,from,eastern,lower,Yangtze,river,belt,China,Here,present,whole,major,trace,element,studies,magmatic,Long,constrain,their,timing,sources,tectonic,settings,results,showed,that,two,plutons,were,formed,Early,Cretaceous,206Pb,238U,ages,Ma,respectively,trapped,residual,zircons,mainly,distributed,Ga,intrusions,characterized,by,silicon,minum,Sr,LaN,YN,Yb,falling,into,region,eHf,values,range,indicating,ancient,average,Ti,temperature,slightly,higher,than,those,other,River,Southern,Tanlu,Fault,STLF,Zircon,Ce4+,oxygen,fugacity,sample,These,geochemical,features,indicate,thickened,continental,Eastern,subduction,Comparing,characteristics,western,areas,Lower,Metallogenic,Belt,barren,propose,may,hybridized,very,small,mantle,while,have,experienced,degree,contaminations,metallogenic,differences,between,parts,also,different,portions,crustal,materials

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