Abstract

• Taung Gaung area is situated in Madaya Township, Mandalay Region, Myanmar. It is located approximately 30 km to the northeast of Mandalay, and 26 km northwest of Pyin-Oo-Lwin. The study area, falling in the Shan-Thai Block, lies in the eastern margin of Mogok Metamorphic Belt (MMB) and between the Sagaing Fault in the west and the Shan Scarp Fault in the east. Ordovician limestone is the main ore host rock in the Taung Gaung area. The regional trend of the rocks is generally N-S with dips either to the east or west forming asymmetrical anticlines and synclines. The major faults also trend N-S following the regional trend. The Ordovician limestone unit trends N-S and is broadly folded into a major anticline. The colour of limestone along the mineralization zone changes from pale blue to yellowish brown due to the effect of alteration. The mineralization follows the anticlinal axis of the major anticline, characterized by shearing and brecciation. The dominant alteration is dolomitization accompanied by minor silicification. Others are pyritization and limonitization. The principal ore mineral in Taung Gaung lead deposit is galena associated with sphalerite and minor amounts of anglesite, cerussite, jalpaite, marcasite and pyrite. In a separate paragenesis, copper as chalcopyrite, tetrahedrite - tennantite, covellite, chalcocite and azurite-malachite are also found in this area. The gangue minerals include limonite, siderite, ankerite, barite, dolomite, calcite and quartz. By the field observation and under microscopic study, several styles of mineralization were found to have formed under variable conditions, such as lead-zinc minerals occurring as disseminations, replacement ore, fracture - fillings and mineralized solution collapse breccias.