This work was jointly supported by the National Natural Science Foundation of China(Grant No.49972026);the Guangdong Natural Science Foundation(Grant No.990531);the project of the ChineseAcademy of Sciences(Grant No.KZCX2-SW-117);the Chinese National Key Project for Basic Research(Grant No.G1998040807)and US NSF.
Our two newly obtained high-quality 40Ar/39Ar ages suggest that the high-K volcanic rocks of the Lawuxiang Formation in the Mangkang basin, Tibet were formed at 33.5 ( 0.2 Ma. The tracing of elemental and Pb-Sr-Nd iso...