Zhangjiaping Fm

Zheng Guobao et al named it in 1963. The named section is located in Zhangjiaping, Leiyang, Hunan. The reference section is located in Qijia-Yijia, Leiyang, Hunan. Lowermost formation in Daye Gr.

Synonym: Before naming, the strata represented by this group had been named the "Sifang Well Group" (Beijing Institute of Geology, 1959).

It is mainly composed of sand shale and limestone, which can be divided into two lithologic sections. The lower part of the lower member (Qijia member) is mainly composed of yellow and yellow-green shale and thin layer limestone, with a small amount of marl, siltstone and fine sandstone between them. In the middle, the yellow shale is interbedded with gray fine sandstone and limestone lens, and the upward fine sandstone is increased and turns yellow. The upper part is dark gray thin to thick limestone interbedded with yellow shale, the thickness of this segment is 174 to 370 m. The upper member (Luojia member) is mainly composed of grey-green, yellow and yellow-green sandstone and shale interbedded with marl with a thickness of 165 to 174 m.

Ammonoids: Leiophyllites sp., L. chamunda, Ophiceras sp., Prionolobus sp., Flemingites sp., Pseudoflemingites sp. and Meekoceras sp.; Bivalves: Claraia aurita, C. griesbachi concentrica, C. griesbachi, Pseudoclaraia wangi, Posidonia sp., P. circularis, Claraia clarai, C. aff. aurita.