A sequence of fliuviolacustrine deposits, named the XigedaFormatiom, with an approximate thickness of 411 m, is dis-tributed on a valley shoulder about 920 m above the waterlevel of the Dadu River in Haiziping, Luding, western Sichuan,on the inner side of the southeastern boundary belt of the WestSichuan Plateau. A preliminary study of the magneto-stratigraphic column suggests that the upper and lower parts