The La-ICPMS U-Pb Ages of Detrital Zircons from the BAYANKALA Group: Implication for the Provenance

摘要

Songpan-Ganzi Orogenic belt is covered by thick Triassic turbidite complex-Bayankala Group. The provenance of Triassic turbidites is still controversial. In order to constrain the detrital provenance of the siliciclastic rocks, We carried out La-ICP-MS zircon U-Pb dating and Hf isotope analyses on 44 detrital zircons obtained from Bayankala group. There are three peak values for, i.e. 247-500Ma, 1711-2000Ma, and 2200-2580Ma. On the basis of regional geologic background. We suggest that the the formation age of Bayankala Group was derived mainly from Qinling, Qilian, and Kunlun orogens along the southern margin of the North China Craton with minor the South China.