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.