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The origin and tectonic settings of metasedimentary sequences in the Central Asian Orogenic Belt have been a matter of debate regarding their contributions with some proposals of being microcontinents or accreted material, largely due to a lack of high resolution geochronological data.This paper reports detrital zircon U-Pb age and Hf isotopic data for the previously mapped Precambrian metasedimentary rocks from the Beishan orogenic collage,southern Altaids.Our data show that Precambrian ages dominate all the analyzed samples, hut two samples yield Paleozoic zircons which suggest that they were not deposited in the Precambrian.The late Paleoproterozoic-early Mesoproterozoic group(-2000-1300 Ma)is the largest age population among the six samples analyzed.This age population(-2000-1300