Entity

Time filter

Source Type


Li Z.-H.,Cheng du Institute of Geology and Mineral Resources | Lin S.-L.,Cheng du Institute of Geology and Mineral Resources | Cong F.,Cheng du Institute of Geology and Mineral Resources | Zou G.-F.,Cheng du Institute of Geology and Mineral Resources | Xie T.,Cheng du Institute of Geology and Mineral Resources
Bulletin of Mineralogy Petrology and Geochemistry | Year: 2012

Lots of granitoides are distributed in Tengchong-Lianghe area, western Yunnan Province. In this paper, zircon LA-ICPMS U-Pb dating and Hf isotopic compositions of zircon were carried out on monzonitic granite from Lianghe area. Zircons with Th/U ratios rang from 0.34 - 1.65 and clear oscillatory zoning indicate typical magmatic genesis. Zircons U-Pb dating from one sample yielded concordant ages of 139. 6±2. 3 Ma, 129. 7±5. 2 Ma and 118. 8±4. 2 Ma, indicating that there were mult-episodes magmatism in Tengchong-Lianghe block in Early Cretaceous. Insitu Hf isotopic analyses yielded εHf(t) values rang between-20.15 and -30.65, corresponding to Hf isotopic crustal model ages, (tDM C) of 2458 - 3083 Ma. It implies that the source of monzonitic granite was derived from older crust partial melting. Combined with the detrital zircons of 2503 Ma age from the Gaoligongshan gneisses, indicate the presence of early Precambrian basement in the Tengchong-Lianghe Block. It is proposed that the early Cretaceous magmatic belt in Tengchong-Lianghe black resulted from the sortherward subduction of the Bangonghu-Nujiang oceanic lithosphere underneath the Tengchong-Lianghe black. Source

Discover hidden collaborations