The SHRIMP zircon U-Pb dating and geological features of Bairendaba diorite in the Xilinhaote area, Inner Mongolia, China. G

The diorite in Bairendaba Ag polymetallic ore district was studied with SHRIMP zircon U-Pb and geochemical method. It has yielded a Hercynian emplacement age of 326.5±1.6Ma (MSWD=1.7), and the geochemical data suggest a volcanic arc setting genesis for the diorite, there was significant contamination with Xilinhaote complex in the magma evolvement. Combined with the geological and geochronological features of granitods in the nearby area, it shows that there has been an intensive Hercynian tectonic-magmatic event in this area, and the volcanic arc setting may extend from Sunid area to northern Hexigten.