LA-ICP-MS zircon U-Pb age dating of the Sanlichen intrusion in the Sujiawan region, eastern Anhui

The Sanlichen intrusion is located in the central part of the Chuxian-Lujiang copper-gold metallogenic subzone in the Middle-Lower Yangtze River Valley metallogenic zone, where diorite and granodiorite are accentuated. The present paper presents two groups of high-resolution zircon U-Pb ages:126.9±1.8 Ma for the diorite and 126.0±1.0 Ma for the granodiorite. Both the diorites and granodiorites are originated from the Early Cretaceous magmatic activity. The inherited zircon U-Pb ages mainly range from 2.5 to 1.9 Ga, and the peak age is about 2.0 Ga. These data show that the magmas may be derived from the South China plate, with the mixtures of the North China plate. The similarities in mineralization age and lithology between the Sanlichen intrusion and the copper-gold deposits, and those in alteration and mineralization between the Sanlichen intrusion and the country rocks show that the intrusive rocks should be the products of the same tectonic-magmatic-mineralization events. The Sanlichen intrusion and its surrounding areas are believed to be prospective for the exploration of the skarn-type copper-gold deposits.