///Located in the northern margin of the Jiangnan orogen(south of the Yangtze River), Zhanggongshan area of Anhui-Jiangxi border region contains very thick low greenschist-facies metamorphic flysch rocks dominated by argillo-calcareous fine-grained elastic rocks with minor volcanic materials. High precise isotopic dating shows that it was probably formed in Neoproterozoic between 821-840 Ma. Detrital zircon U-Pb ages are largely 826~2 600 Ma, showing evidently 5 peaks, i.e., 2500Ma, 2000~2 200 Ma, 1 800 Ma, 958 Ma and 827~841 Ma, dominated by young detrital zircons whose ages are very close to ages of volcanic rocks interbeded with clastic rocks, indicating that epimetamorphic rocks mainly resulted from contemporary igneous rocks. Differences in content and ratios of large-ion lithophile elements such as(LILE), Rb, Cs, Sr, Ba and Th, together with variations of Sr isotopic characteristics, suggest that Xikou Group and Shuangqiaoshan Group detrital rocks experienced different tectonic evolutions.