Analysis and Diagnosis of the Buddhist Wall Paintings in the Josadang Shrine, Buseoksa Temple, Korea

Abstract

Korea’s National Treasure No. 46, the Josadang Shrine of the Buseoksa Temple, was produced in the 3th year of King Woowang’s rein in the Goryeo Dynasty. It is of critical research importance, as it preserves the earliest Buddhist wall painting in Korea. Investigations of the mural identified notable physical damages, such as cracks, peeling and exfoliation of the paint layers, as well as excessively glossy residues and stains left by previous fixing attempts. The wall paintings are mainly affected by traverse cracking, but cracks, peeling and other forms of damage are also present in an area where a reinforcing mortar was used. Since salt deterioration was also associated with the reinforced area, correction measures are required. It is difficult to understand fully the nature of the wall painting stratigraphy because it is concealed by a wooden frame applied during the Japanese colonial period. The structure of the wall paintings was therefore determined by carrying out ground penetrating radar (GPR). At least two earth-based layers are present. Ultrasonic testing revealed that the wall paintings generally have good physical properties. However, ultrasonic velocities were very low around cracks on the mortar-reinforced parts, implying poor conditions in these areas. In addition, thermal imaging identified areas of internal plaster separation. Surface moisture measurements varied on the wall paintings, partly according to when these were made. On the other hand, surface temperature readings of the wall paintings tended to decrease consistently in sequence from left to right, regardless of the measurement period.