The granites from the Huangcaoling region, Luchun, Yunnan: SHRIMP zircon U-Pb chronology and geological implications

The present paper deals with the SHRIMP zircon U-Pb chronology, major and trace element geochemistry, and obtain a SHRIMP zircon U-Pb age of 249.8±4.3 Ma for the granites from the Huangcaoling region, Luchun, Yunnan. Geochemically, the granites in the study area display normal anomalies of K, Rb, U, Th and Pb, and negative anomalies of Nb, Ta, Ti, Hf and Eu, indicating the peraluminous, high-K cala-alkaline S-type granites formed in the island-arc tectonic setting. During the Early Triassic, there once occurred the westward subduction of the Ailaoshan Ocean, and the transition from the mature island arc to the continentcontinent collision in the Luchun region, Yunnan.