Mineralogy of the Mudeungsan Tuff (Republic of Korea) Using Synchrotron X-ray Powder Diffraction and Rietveld Quantitative Analysis

Mudeungsan (Mount Mudeung) is an extinct volcano located in the southwestern part of South Korea that was formed Late Cretaceous period. This mountain, 1187 m above sea level, adjacent to Gwangju Metropolitan City, which has a large population (about 1.4 million) and volcanic rocks, including columnar joints, form various types outcrops. Although this mountain listed as national geopark 2014 UNESCO Global Geopark 2018, much basic research yet be carried out. In particular, there are no mineralogical studies rock samples despite well-preserved variety rocks. For study, X-ray diffraction analysis conducted using from joints known tuff. We report rocks mostly dacite, mainly composed quartz, plagioclase, sanidine through Rietveld quantitative analysis. α-cristobalite, crystalline polymorph silica, appears joint indicating experienced explosive eruption during formation mountain.