Quy Lang Fm

The type section is located on the road from Tri Lc Village through the Quy Lang Village (abandoned) to Highway N°lA (N= 19°00’; E= 105°25'). It was named by the name of Quy Lang Village, Yen Thanh District, Nghe An Province, crosscut by the stratotype.

Synonym: ỉỉệ tầng Quy Lăng: Jamoida A.I., Mareichev A.M. (in Dovjikov A.E. et al. 1965 - Ladin-Cami); VQ Khúc (in Vũ Khúc et al. 1965 - Ladin-Cami), (in Vũ Khúc, Bùi Phú Mỹ et al. 1990 - Trias gi^a), (in Vũ Khức et ai. 2000 - Ladin); Đặng Trần iluycn (in Tống Duy Thanh ei a/. 1995 - Ladín); Lê Duy Bách, Đặng Trần Quân et al. 1996; Đặng Trần Quân, Lề Duy Bách, Nguyễn Văn I ỉoành et al. 1996. - Diệp Quy Lăng (part.): Vũ Khúc, Trịnh Thọ 1969 (Ladin); Vũ Khúc 1980, 1984, 1990 (Ladin).. - Schistes trìasiques (part,): Jacob c., 1921. - Bậc Ladín: Vũ Khúc, Trịnh Thọ (in Trần Văn Trị et al. 1977)

Calcareous claytone with thick limestone interbeds in the lower part. Characteristic section in Thanh Hoa Province is: (1) Greenish-gray, thin-bedded marl, calcareous sandstone with lenses of blak-grey limestone; 140 m thick, containing Ladinian bivalves of Costatoria goldfussi, C. ngeanensis, Trigonodus tonkinensis, Cercomya magma, etc. (2) Brownish, fine-grained sandstone, dirty-yellow siltstone, greenish-grey claystone, red-brown siltstone; 200 m thick. (3) Greenish-gray claystone, in places containing carbonate concretions, interbedded with siltstone grading upwards into yellowish-grey shale, 320 m thick, containing Ladinian bivalves of Costatoria goldfussi, Hoernesia magnissima, Cercomya magma, etc.

Ladinian bivalves: Trigonodus tonkinensis, T. trapezoidalis, T. keuperinus, T.zhamoidai, Hoernesia magnissima, Costatoria gold/ussi, C. ngeanensis, C. aff. proharpa), Langsonella cf. minima), Aviculopecten sp., Entolium sp