Abstract

• The Thitsipin Limestone Formation extensively covers the entire Shan State. The present investigated Hti Ta Hkaw area, is situated in Taunggyi Township, southern Shan State. The formation is characterized by thin-bedded to massive, bluish grey to dark grey limestone and dolomitic limestone with abundance of shallow marine fauna. The classification of microfacies is based on the presence and proportion of skeletal and nonskeletal components. Based on the detailed petrographic analysis, nine microfacies have been recognized comprising coral boundstone, bioclasticrudstone, algal packstone-grainstone, fusulinidpackstone, peloidalpackstone, intraclasticwackestone-packstone, foraminifer wackestone, lime mudstoneand dolomitic lime mudstone. On the basis of the observed microfacies types, the Thitsipin Limestone Formation would have been deposited in the rimmed platform condition under sub-environments of intertidal, subtidal channel lag, subtidal lagoon, back reef lagoon and open marine environment during the Middle Permian time.