Abstract:Objectives: The Muce monzonite in Xiong’er Mountains is distributed in the southern margin of the North China Craton. It is of great geological significance to study the tectonic evolution of the southern margin of the North China Craton. Combined with petrological study, geochemical characteristics of the monzonite and the LA-ICP-MS zircon U-Pb age, we briefly discuss the formation age, origin and tectonic background of the monzonite. Methods: Based on the field work, through the microscope observation, the whole rock chemical analysis and LA-IPC-MS U-Pb zircon dating of Muce monzonitic feldspar and monzogranite were carried out. Results: The geochemical analysis of the Muce monzonite shows that that belongs to type A genetic type and is formed in the rifting environment under the extensional structure. The monzonite is riched in large ion lithophile elements (LILEs) Rb, Ba, Sr, Pb and light rare earth elements (LREEs). The monzonite is deficient in high field strength elements (HFSEs) Th, Nb, Zr, and strong depletion of Ti and Ta, which show the characteristics of typical island arc magmatic rocks. LA-ICP-MS U-Pb zircon dating of the monzonite samples yield the ages of 2172±8 Ma (MSWD=0.58, n=17) and 2186±7 Ma(MSWD=0.60, n=19). Respectivesly, monzogranite sample gets a LA-ICP-MS U-Pb zircon age of 2174±8 Ma(MSWD=0.45, n=19), indicating the Muce monzonite was formed in Paleoproterozoic. Conclusions: Combined with the previous study, it is considered that the Muce monzonite was formed in the Paleoproterozoic and may have experienced the influence of rifting and island arc.