Abstract

• The Triassic outcrops in northern Shan State have received relatively little study compared to correlative strata in the southern Shan State. Tirassic section to the west of Lashio, northern Shan State encompasses the Late Permian to Middle Triassic Nwabangyi Dolomite Formation. The marine reptile bearing limestone is the sandwiched unit of the Nwabangyi Dolomite Formation. Two specimens of Pachypleurosaurs are the only identifiable fossil collected from this limestone unit. It can be divided into four main facies (in ascending order); sedimentary breccias, laminated limestone, thin to medium-bedded limestone and thin-bedded, limestone intercalated with siltstone and shale. The exact stratigraphic position of the CMLV-1 Specimen is not known because of quarrying in this locality. YDBGLV-4 specimen bearing beds are medium-bedded, grey to dark grey, fine- to medium-grained limestone unit lie between the thin-bedded and laminated limestone facies. This limestone unit apparently grades into the surrounding dolomites.