Zircon U-Pb SHRIMP Dating of the Monzonite Granite-Porphyry from the Bangpu Large Porphyry Molybdenum-Copper Deposits,Tibet,and its geological Significance
The zircon U-Pb SHRIMP technique was applied to measure the age of the monzonite granite-porphyry from the Bangpu porphy deposits in the eastern Gangdese porphyry belt.It was obtained that the 206Pb/238U mean age is 13.9±0.3 Ma(MSWD =3.05),which belongs to the late period of Himalaya.The Bangpu monzonite granite-porphyry was formed during the period of ore-bearing porphyries forming in the Gangdese metallogenic belt to the extension environment of post-collision(12~18 Ma).Our new data suggest that the Bangpu monzonite granite-porphyry shared similar metallogenic dynamics settings to the Gangdese copper belt,which belongs to a rapid outbreak of large-scale mineralization process.Our new result is very important in confirming the active time of the Gangdese magma,provides chronological data and new inspiration for evolution studies of the whole Gangdese metallogenic belt.