Diagenetic and mineralization chronology study of the Wujiaping tin ore deposit in Nanling Range

Wujiaping tin ore deposit is a greisen-type deposit with medium-sized prospect scale newly discovered in Dayishan area in recent years. The orebody occurs as a vein in the Dayishan compound granite body and is controlled by NE-trending faults. In order to determine its diagenetic and metallogenic age, summarize the metallogenic regularity in Dayishan area, and guide regional prospecting and exploration, the LA-ICP-MS zircon U−Pb dating of medium-coarse grained porphyritic biotite monzonitic granite (PM21-19) and medium-fine grained porphyry biotite monzonitic granite (PM21-27) in ore-bearing surrounding rocks was studied. The diagenetic ages of 157.1 ± 1.1 Ma (MSWD=0.55) and 153.7 ± 1.2 Ma (MSWD=0.55) are obtained, which belong to the early Yanshanian period. At the same time, the Rb−Sr isochron age of quartz in the greisen-type tin ore is 148.1 ± 2.1 Ma (MSWD = 0.52). Combined with the regional data, the diagenetic and metallogenic age of Wujiaping tin ore deposit is the early Yanshanian period, which belongs to the peak of Mesozoic diagenesis and mineralization(160~150 Ma) in Nanling region.