Petrological Study and Provenance Estimation on the Stone Materials of the Naju Eupseong Dongjeommon Gate, Korea

This study is based on the mentorship course in CNU Science Education Institute For the Gifted. The Naju Eupseong Dongjeommun Gate, which was built in the Goryeo Dynasty, was restored in 2002, but a heterogeneous stone material that showed a significant difference from the original stone of the fortress wall, was used as the restoration stone. This study aims to clarify the difference between raw stones and restored stones by the investigation of the petrological features of the stone materials for the Naju Eupseong Dongjeommun Gate, and to estimate the provenances of the raw stones through the geologic survey. In addition, replacement stones that can be used for when the Naju Eupseong Dongdaemun Gate is renovated are presented. As a result of measured magnetic susceptibility and visual observation, the stone materials of the Naju Eupseong Dongjeommun Gate consist of granodiorite, and granite gneiss. Compared to the original stone, the restored stone is judged to be a granite, which shows a clear difference in the petrographical features such as the results of visual observation and the magnetic susceptibility. As a result of the geologic survey around Naju Eupseong Walled Town, the area of Geumseongsan Mountain in Naju is presumed to be the source of the original stones. Granite diorite is considered appropriate as a substitute stone if the restoration of Naju Eupseong Dongjeommun Gate is carried out.