Numerous intrusive bodies of mafic-ultramafic to felsic compositions are exposed in association with volcanic rocks in the Late Permian Emeishan large igneous province(ELIP),southwestern China.Most of the granitic rocks in the ELIP were derived by differentiation of basaltic magmas with a mantle connec-tion,and crustal magmas have rarely been studied.Here we investigate a suite of mafic dykes and Ⅰ-type granites that yield zircon U-Pb emplacement ages of 259.9±1.2 Ma and 259.3±1.3 Ma,respectively.The sHf(t)values of zircon from the DZ mafic dyke are-0.3 to 9.4,and their corresponding TDM1 values are in the range of 919-523 Ma.The eHf(t)values of zircon from the DSC Ⅰ-type granite are between-1 and 3,with TDM1 values showing a range of 938-782 Ma.We also present zircon O isotope data on crust-derived felsic intrusions from the ELIP for the first time.The δ18O values of zircon from the DSC Ⅰ-type granite ranges from 4.87‰ to 7.5‰.The field,petrologic,geochemical and isotopic data from our study lead to the following salient findings.(i)The geochronological study of mafic and felsic intrusive rocks in the ELIP shows that the ages of mafic and felsic magmatism are similar.(ii)The DZ mafic dyke and high-Ti basalts have the same source,i.e.,the Emeishan mantle plume.The mafic dyke formed from magmas sourced at the transitional depth between from garnet-lherzolite and spinel-lherzolite,with low degree partial melting(＜10％).(iii)The Hf-O isotope data suggest that the DSC Ⅰ-type granite was formed by par-tial melting of Neoproterozoic juvenile crust and was contaminated by minor volumes of chemically weathered ancient crustal material.(iv)The heat source leading to the formation of the crust-derived fel-sic rocks in of the ELIP is considered to be mafic-ultramafic magmas generated by a mantle plume,which partially melted the overlying crust,generating the felsic magma.

Hao Zou;Cheng-Hui Hu;M.Santosh;Hai-Feng Chen;Chang-Cheng Huang;Xin-Wei Chen;Hong-Kui Li;Xin Jin;Li-Ming Yu;Min Li

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;Key Laboratory of Tectonic Controls on Mineralisation and Hydrocarbon Accumulation of Ministry of Land and Resources,Chengdu University of Technology,Chengdu 610059,China;School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China;Department of Earth Science,University of Adelaide,Adelaide,SA 5005,Australia

地学前缘（英文版）

[1]Hao Zou;Cheng-Hui Hu;M.Santosh;Hai-Feng Chen;Chang-Cheng Huang;Xin-Wei Chen;Hong-Kui Li;Xin Jin;Li-Ming Yu;Min Li-.Crust-derived felsic magmatism in the Emeishan large igneous Province:New evidence from zircon U-Pb-Hf-O isotope from the Yangtze Block,China)[J].地学前缘（英文版）,2022(03):139-155

sHf,petrologic

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