This study focuses on the disintegration characteristics of sampled mudstone from the Matoushan group (K2m)

the Tuodian group (J3t) and the Lufeng group (J1l)

Yunnan province of Southern China. These sampled rocks are subjected to the treatments of wetting-drying (WD)

wetting-drying + refrigerating-heating (WDRH) and refrigerating-heating (RH) under laboratory condition

respectively. The fractal dimension method is applied to analyze the disintegration characteristics of the sampled mudstone. The results show that the fractal dimension exactly described the disintegration characteristics of purple mudstone. The larger fractal dimension value is

the higher the degree of rock fragmentation is. The rank order of the fractal dimension of the three treatments is WDRH WD RH

and is significantly different between the treatments

indicating the effect of hydrothermal on mudstone is greater than the influence of just water or heat. The rank order of the fractal dimension of three purple mudstones is J3t J1l K2ms

and significantly different between the J3t

J1l and K2m under WD and WDRH

resulting from physical characteristics

chemical elements composition and weathering maturity.