Geochemical characteristics and genesis of Wulong mafic microgranular enclaves in Southern Qinling Mountain

Aim To determine the genesis and source features of mafic microgranular enclaves in Wulong granite intrusion in Southern Qinling.Methods Petrology,major and trace element research.Results An integrated field and laboratory study on the colours,shapes,textures,structures,compositions,mineralogy and petrology of the enclaves indicates that they have coexisted with the host granitic magmas and experienced rapid crystallization.The enclaves are dioritic,and enriched in alkali contents,in the SiO2-K2O diagram,all the samples plotted in the shoshonite area,and the Na2O/K2O1;compared with the host granite,the enclaves have higher magnesium,iron,calcium,titanium.They are enriched in LILE and LREE intensively,with Nb,Ta etc.HFSE elements negative anomaly.Conclusion Mafic enclaves are the products of the mafic magmas intruding in the granitic magmas and mixing with it.The mafic magmas were derived from an enriched mental,which maybe once metasomatized by subduction fluids.In the source area,flogopite were melted and there exist rutiles,amphiboles deficient in Mg and garnets in the residue.