Abstract: The Liziyuan Group exposed on the northern side of the western sector of the Qinling Mountains near Tianshui City was estimated by Zhang Weiji et al.It consists of Neoproterozoic to Early Paleozoic volcano sedimentary sequences that have undergone different degrees of metamorphism.Study of the Liziyuan Group in the vicinity of Guanzizhen has revealed that the group underwent at least two stages of strong destructural deformation. The early stage deformation was marked by nearly E W directed dextral shear accompanied by low greenschist facies metamorphism,while the late stage one by SE directed sinistral shear. 40 Ar 39 Ar dating of the metamorphic mineral biotite implies that the early event took place at the beginning of the Carboniferous（355 Ma B.P.）.