Geochronology of the Dasongpo tin deposit, Yunnan Province: Evidence from zircon LA-ICP-MS U-Pb ages and cassiterite LA-MC-ICP-MS U-Pb age
云南腾冲大松坡锡矿成矿年代学研究:锆石 LA-ICP-MS U-Pb年龄和锡石LA-MC-ICP-MS U-Pb年龄证据

The Dasongpo tin deposit is located in Tengchong-Lianghe Sn-W metallogenic belt in the Sanjiang Tethys metallogenic domain, which is related to Guyong batholith. In the Dasongpo tin deposit, the Xiaolonghe biotite-granite and monzogranite yielded zircon U-Pb ages of 71.5±2.1Ma~75.3±4.2Ma, and 70.3±3.2Ma respectively, likely represents crystallization age of magma. Few researches have reported on the cassiterite LA-MC-ICP-MS U-Pb dating in China and overseas. In order to constrain the timing of metallogenic age better, we carried out cassiterite U-Pb dating for the greisen-type ore with age of 75.5±2.6Ma. The ages of the Xiaolonghe tin-bearing granitoid are similar with those of the Guyong batholith, indicating the tin-bearing granitoid as a part of the Guyong batholith. Metallogenic age is similar with that of tin-bearing granitoid, indicating their formation at the same time from the subduction of the Neo-Tethys Ocean.