Experimental Study on the Self-Healing Behavior of Fractured Rocks Induced by Water-CO₂-Rock Interactions in the Shendong Coalfield

Table 1

Mineral compositions of specimen surfaces before and after the experiment (%).

Rock samples		Quartz	Potassium feldspar	Plagioclase	Clay minerals
Rock character	Experimental stage				Total content	I/S	It	K	C	S%
Coarse-grained sandrock	BE	47	26	24	3	—	2	96	2	—
	AE	50	23	24	3	—	2	97	1	50
Fine-grained sandrock	BE	54	14	24	8	6	12	73	9	10
	AE	57	12	23	8	6	10	78	6	57
Sandy mudrock	BE	39	17	30	14	51	21	16	12	20
	AE	44	14	31	11	50	20	20	10	16

Notes: the table lists the relative proportions of the minerals to the total detected content rather than the overall content since some minerals are undetectable. K means kaolinite, C means chlorite, It means illite, and I/S means mixed illite-smectite layers minerals, and S% is the illite proportion in layers of mixed illite and smectite; BE means before the experiment, and AE means after the experiment.