CSD in crystalline limestone at the Hiraodai Karst Plateau, Fukuoka prefecture, Japan

Abstract

The Hiraodai Karst Plateau is mainly consist of crystalline limestone, and is designated as natural monument, so strictly prohibited from breaking exposure.  We tried to measure the crystal size distribution from the photograph of exposure surface.  According to the relationship between the grain size and temperature discussed in Covey-Crump & Rutter (1989), more than 640 degree of centigrade temperature is estimated.