Water Inrush Mechanism of Roof Induced by the Fault Weakening Effect in the Coal Mining

Table 1

Water quality analysis results.

Sample	pH	Mass concentration of each ion/(mg·L^−1)							Type of water
		Ca^2+	Mg^2+	K^+ + Na^+	Cl^−
T1y-1	7.61	77.21	2.98	10.02	13.12	33.75	286.48	4.80	HCO3-Ca
T1y-2	7.80	70.20	3.68	31.61	10.35	51.04	227.53	6.00	HCO3-Ca
P3c-1	7.70	17.96	67.86	271.22	13.93	264.25	273.17	3.60	HCO3·SO4-Mg·K + Na
P3c-2	8.30	25.48	63.65	143.61	15.42	267.91	199.04	2.40	HCO3·SO4-Mg·K + Na
S-1	7.94	10.65	53.20	129.06	20.49	271.24	248.71	2.80	HCO3·SO4-Mg·K + Na
S-2	8.34	48.42	68.74	101.06	18.01	294.7	246.76	2.80	HCO3·SO4-Mg·K + Na·Ca
S-3	7.87	3.55	50.15	115.98	28.58	196.73	216.37	2.00	HCO3·SO4-Mg·K + Na