[P02-01] Universal geometric fluctuation in fracture patterns of igneous rocks
Keywords:Columnar Joint, Igneous rock, Thermal stress fracture, Polygonal pattern, Drone aerial photography
Columnar joint is a regular pattern of cracking in igneous rock that forms an array of slender columns with polygonal cross section. In this study, we considered the geometry of the polygonal crack tessellation observed at the outcrop surface of columnar joints. Aerial photo shooting of the columnar joint was conducted at four different sites in Japan. Using the primary data, we compared the statistical properties of the polygon geometry between the four sites. The results imply a universal fluctuation in the skewness of polygons, which quantifies the geometric discrepancy in the polygon shape from the regular counterpart.