Zircon SHRIMP Dating and Geochemical Characteristics of Granites in the Eastern Part of the Bayan Har Mountains
巴颜喀拉山东段花岗岩锆石SHRIMP定年及其地球化学特征

In the eastern part of the Bayan Har Mountains, granites with the SHRIMP U-Pb age of 218197 Ma directly intruded folded Triassic strata and are unconformably covered by Jurassic Nianbao Formation. These granites, composed of granodiorite, adamellite and syenogranite, have porphyritoid or porphyritic texture and abundant aluminum and potassium. In addition, they are characterized by lots of biotites, some aluminum-rich minerals such as garnets and tourmalines, and some gray fine dioritic inclusions. With A/CNK 1.001.22, they should belong to CPG-type granite in Barbarin's classification. They were formed at the late stage of Bayan Har intracontinental orogenic activity.