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

Table 2

Contents (mg/L) of major ions and pH values of the water solution before and after the experiment.

Experimental stage		Na^+	SO4^2-	HCO3^-	Cl^-	NH^4+	K^+	Ca^2+	Mg^2+	PH
Before the experiment	Original solution	769.4	1434.8	10.3	5.6	—	0.1	0.1	—	6.24
After the experiment	Experiment with coarse-grained sandrock	1007.4	2543.7	443.55	37.2	16.7	13.1	329.3	40.2	7.42
	Experiment with fine-grained sandrock	1071.5	2129.6	626.1	86.9	8.6	12.6	172.7	35.3	7.68
	Experiment with sandy mudrock	858.4	1367.7	817.8	34.6	2.5	11.8	119.7	232.6	7.33