Geochronology and Geochemistry of Felsite Dike from Shanmen Silver Deposit in Central Jilin Province, China, and Its Geological Significance

Shanmen silver deposit is located on the south section of Daheishan horst polymetallic mineralization belts in central Jilin province, Northeast China. The supplies not only greatest portion and a significant amount gold also. exhibits closely spatiotemporal relationship with Mesozoic ore-hosting diorite granite intrusions basic-felsic dikes. Among dikes felsite one occurred at same fault zone as silver-bearing veins deposit, implying that dike has an important theoretical ore-prospecting significance. Here, we mainly investigate based zircon LA-ICP-MS U-Pb geochronology, petrochemical compositions. Zircon dating from yielded weighted mean age 163.1± 2.3 Ma, which slightly younger than ore-hosted quartz (167.6± 1.9 Ma) monzonite (167.0 ± 1.5 Ma), indicating petrogenetic late Jurassic. Major element data suggest granodioritic granitic chemical composition, belonging to high-K calc-alkaline shoshonite series, SiO2, K2O+Na2O, Al2O3, TiO2, CaO MgO contents ranging 62.98-79.18%, 4.13-5.3%, 13.31-16.01%, 0.05-0.57%, 0.15-3.07%, 0.28-1.8%, respectively. Felsite enriched Rb, U, Pb, depleted Ba, Nb, Sr, Ti other high field strength elements. REE are range 28.42-214.23 ppm, showing weak negative Eu anomalies Eu/Eu* ratios 0.24-0.61. Except for altered sample SiO2 content 79.18%, distribution characteristics trace elements rare earth similar those intrusion diorite. geochemical features show Jurassic was formed tectonic background active continental margins associated subduction Paleo-Pacific Plate. underplating mantle-derived magma caused partial melting meta-sediment lower crust materials form mid-late magmatism mineralization.