Sequence stratigraphy and lithofacies paleogeographic evolution of Katian Stage - Aeronian Stage in southern Sichuan Basin, SW China

ZHU Yiqing,CHEN Gengsheng,LIU Yong,SHI Xuewen,WU Wei,LUO Chao,YANG Xue,YANG Yuran,ZOU Yuanhong

Table 1 Lithological classification for the Katian-Aeronian stages in the southern Sichuan Basin.

Class Sub-class Grain type Diameter of quartz grain/μm Mineral content/% Quartz Feldspar Calcite Dolomite Clay Siliceous shale Siliceous shale Dominated by authigenic quartz 0.5-4.0 ≥50 ≤10 ≤10 ≤10 ≤10 Clay-bearing siliceous shale Dominated by authigenic quartz 0.5-2.0 ≥50 ≤10 ≤10 ≤10 10-25 Feldspar-bearing siliceous shale Dominated by authigenic quartz 0.5-2.0 ≥50 10-25 ≤10 ≤10 ≤10 Calcite-bearing siliceous shale Dominated by authigenic quartz 0.5-4.0 ≥50 ≤10 10-25 ≤10 ≤10 Dolomite-bearing siliceous shale Dominated by authigenic quartz 0.5-4.0 ≥50 ≤10 ≤10 10-25 ≤10 Clayey shale Siliceous clayey shale Dominated by terrigenous grain ≥8 25-50 ≤10 ≤10 ≤10 25-50 Feldspathic clayey shale Dominated by terrigenous grain ≥8 ≤10 25-50 ≤10 ≤10 25-50 Calcareous clayey shale Dominated by terrigenous grain ≥8 ≤10 ≤10 25-50 ≤10 25-50 Argillaceous siltstone Argillaceous siltstone Dominated by terrigenous grains 20-50 25-50 ≤10 25-50 Limy mudstone Limy mudstone Dominated by micritic calcite 20-40 ≤10 ≤10 ≥50 ≤10 25-50