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

Fig. 4. Sedimentary structure plate for the Katian-Aeronian stages. (a) Well ND216, 2325.4 m, top of Pss1, two sets of bentonite; (b) Well JYT1, 4322.3 m, top of Pss2, wavy calcite vein; (c) Well WD213, 3747.3 m, Pss3, biosilica stringer, dominated by radiolarian; (d) Well ND210, 2299.8 m, Pss4, closely-spaced, very thin lamina; (e) Well LU202, 4311.5 m, Pss5, gradually changed lamina belt; (f) Well ZU205, 3344.4 m, base of Pss6, association of bentonite, silica stringer and pyrite; (g) Well ZI211, 3774.1 m, Pss7, pyrite syn-sedimentary crumpling; (h) Well ND213, 2524.0 m, middle and upper parts of Pss7, small-scale Bouma sequence; (i) Well ZU208, 4345.5 m, Pss8, barite nodule; (j) Well ND211, 2223.5 m, Pss8, small-scale Bouma C layer; (k) Well Y101H41-2, 4071.4 m, Pss8, calcareous siltstone.