Middle-Late Triassic sequence stratigraphic framework and sedimentary facies in the Ma’antang section,Jiangyou,Sichuan

The present paper gives a detailed description of the Ma'antang Middle-Upper Triassic stratigraphic section in Jiangyou,Sichuan.The Middle-Late Triassic strata in the section are assigned,according to rock associations referenced from the national lithostratigraphic classification, to the Tianjingshan and Ma'antang Formations which are subdivided into four sequences including SQ1,SQ2,SQ3 and SQ4 corresponding to the third-order sequences.The systems tracts in each sequence are also discussed.