SINGLE-GRAINED ZIRCON U-Pb AGE OF THE CHANGTE'AOBAO GRANODIORITE IN CENTRAL INNER MONGOLIA

The Changte aobao granodiorite is located in the south of Sonid Zuoqi,Central Inner Mongolia.The high precision single-grained zircon U-Pb age is dated as 362±4 Ma (MSWD=0.005),confirming that the pluton was formed in the middle of Late Paleozoic era.Based on this and other isotopic data,the granotoids formed in the middle of Late Paleozoic can be divided into two belts from north to south.