Fig. 8

Schematic diagram of the upper and lower colonnades showing columnar joints and column parameters. a Columnar joints growing from the top and bottom of the tuff emplacement result in the upper and lower colonnades with smaller and larger face widths, respectively. The figure is modified from Grossenbacher and McDuffie (1995). b The column parameters used in this study. Fw and r are the face width and radius of the circle enclosing a column cross section, respectively. The pentagon and circle reflect a perspective effect. The column was in the Sinseon-dae colonnade, and the water bottle is approximately 20 cm in height