Crack Evolution Characteristics and Cracking Mechanism of Red Beds in Central Sichuan during Seepage and Swelling

Table 1

X-ray diffraction results (unit: %).

Lithology	Montmorillonite	Illite	Chlorite	Kaolinite	Calcite	Hematite	Quartz	Albite	Plagioclase
Mudstone	20	15		5		1	38	21
Argillaceous sandstone	5	13	5		2	3	37	27	8
Sandstone		11	4	12	3		31	27	12