• "[Lower Kazanian Substage - Baitugan Beds - Lingula Shale Member]

•Package A1/4 Interval 7.10 - 7.45m Thickness 0.35m

•Shale: greenish-grey, calcareous, soft, flexible, with numerous (up to 40% of bulk rock) well preserved shells of brachiopods, and fragments of branched bryozoans.

•Package A1/5 Interval 7.45 - 7.50m Thickness 0.05m

•Limestone: grey and dark-grey with slight reddish and greenish tints, fine-grained, solid. The top surface is uneven which is caused by the shells of Dielasmatidae in situ and small algal-microbial mounds. Foraminifers, ostracods, gastropods, brachiopods and fragments of branched bryozoans. The number of bioclasts significantly decreases from the base to the bed top.

•Package A1/6 Interval 7.5 - 20.5m Thickness 13.0m

•Shale: grey and dark-grey with slight greenish and yellowish tints, thinly bedded, platy. Thin interbeds (5cm) of concretionary limestones and marls occur at the different levels. From the bottom to top, the lamination changes from thinly to medium and thick bedded. Some bedding planes contain assemblages of marine ostracods, inarticulate brachiopods, bivalves, branched and fenestrated bryozoans, and charred plant debris. The lowermost part of the package contains the brachiopod Licharewia rugulata and the conodont Kamagnathus khalimbadzhae, the index species defining the bistratigraphic bondary of the Kazanian Stage." (Nurgaliev et al. 2015)