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The Mesozoic magmatic activities of the Zijinshan orefield included Late Jurassic and Early Cretaceous Episodes.The first episode of magmatic activity occurred in Late Jurassic(154～149 Ma)in a compression environment,characterized by the intrusion of Zijinshan composite granite body and Caixi pluton of S-type granite.The Zijinshan composite granite body has 3 pulsations,which occurred in 154 Ma,150 Ma and 149 Ma.Caixi pluton intrusion occurred around 150 Ma.The magmatic activity of the second episode was composed of four stages during 125～93 Ma in Early Cretaceous in a tension and mantle upwelling environment,forming a series of I-type granites and their cogenetic heterophase volcanic rocks and subvolcanic rocks and providing metallogenic material and heat.The volcanic eruption and super-hypabyssal magmatic intrusion of the first stage finds expression in the formation of dacite of the Lower Member in Shimaoshan Group and the Zijinshan subvolcanic rocks(125～118 Ma).The volcanic eruption and intrusion of the second stage are characterized by the andesite eruption of Shimaoshan Group and Sifang pluton intrusion as well as the formation of dacite porphyrite(109～103 Ma).The volcanic eruption and intrusion of the third stage are characterized by the dacite eruption as well as the porphyraceous granodioritic porphyry intrusion in Luoboling-Zijinshan together with the formation of quartz dioritic porphyrite near Longjiangting and Ermiaogou(103～100 Ma).The volcanic eruption and intrusion of the fourth stage are characterized by the intrusion of Luoboling prophyry,the eruption of rhyolite in the upper member of Shimaoshan Group and the intrusion of barren vein rocks after the ore-forming period(e.g.,Dayanli granite porphyry dykes,quartz porphyry dykes in Zijinshan gold-copper ore deposit)(100～93 Ma).The Late Jurassic and the Early Cretaceous co-magmas respectively differentiated and evolved into varied facies in different areas.