On the Stratigraphic Sequence, Lithological Characteristics and Origin of the Lower Permian Pangduo Group in Lhunzhub County, TibetJI Zhansheng, YAO Jianxin, WU Guichun, ZHAN Lipei, JIANG Zhongti and FU Yuanhui(Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037; Geologica] Physical Data Center, Ministry of Land and Resources, P. R. China, Hebei 065201; China University of Geosciences, Beijing 100083)The paper deals with the sequence and lithologi…