Experimental Study on the Permeability of Weakly Cemented Rock under Different Stress States in Triaxial Compression Tests

Table 4

Results of composition analysis in specimens using X-ray.

Lithology	Quartz (%)	Kaolin (%)	Montmorillonite (%)	Illite (%)	Other (%)	Clay minerals (%)
Mudstone	73.13	15.09	2.24	4.56	4.98	21.89
Shaly coarse sandstone	79.90	4.50	—	6.15	9.45	10.65