Sedimentary characteristics of the Nanchuan bauxite deposit, Chongqing

A succession of basal conglomerates at the base and distributary channel deposits at the uppermost part of the bauxite-bearing rock series in the Nanchuan region have been recognized on the basis of the investigation of abundant field outcrops in Nanchuan, Chongqing. Sedimentary facies analysis on the basis of lithology and contents of the elements such as B, Sr, Ba, Ga, Rb, MnO and TiO₂ shows that the Nanchuan bauxite deposit is assigned to the sedimentary bauxite deposit rested in the epicontinental offshore lacustrine environments during the Middle Permian transgressions.