Toe Naing Oo
Department of Geological Engineering, Faculty of Engineering, Gadjah Mada University, Yogyakarta, 55281, Indonesia; Department of Geology, West Yangon University, Yangon, 11181, Myanmar
Agung Harijoko
Department of Geological Engineering, Faculty of Engineering, Gadjah Mada University, Yogyakarta, 55281, Indonesia
Lucas Donny Setijadji
Department of Geological Engineering, Faculty of Engineering, Gadjah Mada University, Yogyakarta, 55281, Indonesia
The Shwebontha prospect area is situated in the Central Volcanic Belt, central Myanmar, where the well-known Sagaing Fault serves as its eastern boundary. This study aims to document key the mineralogy, host rock geochemistry and ore mineralizing fluids. The mineralization, hosted by Upper Oligocene to Middle Miocene rhyolites, displays a strong lithological control. Mineralization is characterized by gold-bearing silicified massive ore and chalcedonic quartz veins in which sulfides are clustered and disseminated not only in quartz gangue but also in rhyolite host rocks. The significant ore minerals in the mineralized veins include pyrite, sphalerite, galena, chalcopyrite, and gold. Common hydrothermal alterations such as silicic, argillic and propylitic alteration types are recognized. According to the fluid inclusion data and interpretation, ore mineralizing fluids in the research area are characterized by formation temperatures of 260-280 °C and salinity of 0.35-2.41 % wt. NaCl eq. respectively. Mixing of hydrothermal fluids was generally considered to be an effective mechanism for ore transport and deposition.
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Copyright © 2023 Toe Naing Oo, Agung Harijoko, Lucas Donny Setijadji
This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.
