Abstract:The rock samples of the typical faults(zones)of Manasi River profile,Houxia profile,and Dabancheng profile were examined in terms of their mineralogical and geochemical components. On this basis,the geochemical distribution and differences in the rare earth elements were analyzed for the fault zone fillings of different trends,and the source and tectonic environment of the fillings of Yilin Heibiergen Fault Zone were studied and assessed. The results showed that the characteristics of the veins of fault zone fillings near Yilin Heibiergen Fault Zone in the study area are similar to those of the rare earth elements of whole rock,demonstrating the relative accumulation of light rare earth elements. The fillings of the nearly EW-trending fault zone came from the deep crust and formed relatively early,which were mainly at the convergence boundary of the plates and resulted from the hydrothermal process of hypo magma. The fillings of the NE-SW trending fault zone,formed relatively late,were developed at the convergence edge of plates and in the tectonic environment of intra-continental collisions,which were the results of shallow crust activities.