This paper presents the geochemical characteristics and isotope chronology of volcanics from Yamansu Formation,occurring in Jueluotage tectonic belt in the eastern Tianshan of China.Petrological,isotope chronology and geochemical features of these volcanic rocks show thathansi-font-family: ’Times New Roman’">:(1hansi-font-family: ’Times New Roman’">)Yamansu Formation is composed of basite-mesite-acidic volcanic rock,pyroclastic rocks and pyroclastic sedimentary rocks.And it is mainly of calc-alkaline series.The geochemical characteristics demonstrated and inherited zircon age suggests that Yamansu volcanic rocks were formed at arc settings with continental basement.hansi-font-family: ’Times New Roman’">(2hansi-font-family: ’Times New Roman’">)In situ zircon U-Pb LA-ICP-MS dating on the zircon of Yamansu Formation yielded an age of 348.0hansi-font-family: ’Times New Roman’">±1.7Mahansi-font-family: ’Times New Roman’">(MSWD=1.15hansi-font-family: ’Times New Roman’">)in the eastern section,335.9hansi-font-family: ’Times New Roman’">±2.4Mahansi-font-family: ’Times New Roman’">(MSWD=1.03hansi-font-family: ’Times New Roman’">)in the middle and 334.0hansi-font-family: ’Times New Roman’">±2.5Mahansi-font-family: ’Times New Roman’">(MSWD=1.02hansi-font-family: ’Times New Roman’">)in the western section,which stands for volcanic age.hansi-font-family: ’Times New Roman’">(3hansi-font-family: ’Times New Roman’">)The magmatic activity started from the east and then developed to the middle and western sections,like the close of scissors.