Daling Fm

It was named by Xie Jiarong and Wang Zhi in 1938. The naming section is situated in the vicinity of Daling, Xiwan, Hexian County, Guangxi.

Synonym: （大岭组）; Tiangtang Fm is now its first member

Being divisible into four members in ascending order: First member (corresponding to the “Tiantang Formation”), composed of light-grey, brown and purple siliceous breccias, the upper part of which locally consists of fine clastics, intercalated with coal beds, with a thickness of 40-350 m. Second member, representing grey, grey-black limestone, containing carbonaceous limestone, intercalated with coal beds, its maximum thickness being of about 127 m. Third member, composed of light-grey thick-bedded bio-limestone, calcirudite and lump limestone, with a thickness of 50-120 m. Fourth member, composed of purple ferruginous siltstone, intercalated with fine-grained clastic quartz-sandstone, locally with marl lenses, with its lower part consisting of grey and yellow-green silty mudstones, with an unknown thickness.

The upper part yields Ostracods and spore-pollen fossils; the second member yields fresh-water-to-brackish-water bivalves, Ostracods, spore-pollen and Chareae fossils; the third member yields fresh-water Ostracod fossils; the fourth member yields bivalves as represented by the Hunanella-Qiyangia assemblage; Ostracods as represented by the Darwinula- Naevicythere assemblage; and spore-pollen fossils as represented by the Classopollis- Chasmatosporites- Klukisporites assemblage.