Zircon SHRIMP U-Pb and biotite Ar-Ar ages from Fujiawu porphyry Cu-Mo deposit, Dexing, Southeast China: implications for magmatic-hydrothermal chronology

The Fujiawu porphyry Cu-Mo deposit, one of the porphyries in Dexing porphyry Cu district, Southeast China, was little know to its magmatic-hydrotermal activities in the past years. The zircon SHRIMP U-Pb analyses of granodiorite show age of 172 +/- 2.1 Ma, two hydrothermal biotite Ar-Ar show ages of 168.7 +/- 1.8 Ma and 169.9 +/- 1.8 Ma, respectively. The data suggests the magma emplaced at about 172 Ma, and the potassic hydrothermal activity occurred at about 169 Ma. The cooling rate of the magma about 150 degrees C per million years.