Groundwater-Mixing Mechanism in a Multiaquifer System Based on Isotopic Tracing Theory: A Case Study in a Coal Mine District, China

Table 2

Chemical composition descriptive statistics of water samples in the study area.

Component	Total sample	Min	Max	Mean	Std. deviation
K^+ (mg/L)	37	0.58	20.89	5.48	5.63
Na^+ (mg/L)	37	10.56	322.05	119.765	118.02
Ca^2+ (mg/L)	37	4.63	195.96	107.64	62.42
Mg^2+ (mg/L)	37	1.12	93.67	26.94	20.84
Cl^− (mg/L)	37	10.04	52.84	31.27	12.09
SO4^2− (mg/L)	37	1.02	626.56	183.88	151.96
HCO3^− (mg/L)	37	218.65	987.29	481.71	197.96
CO3^2− (mg/L)	37	0	21.50	3.35	6.36
pH	37	6.62	9.85	7.55	0.65
TDS (mg/L)	37	303.00	1987.0	734.56	314.18
δ ^18O (‰-SMOW)	37	−11.10	−6.60	−8.26	1.10
δD (‰-SMOW)	37	−85.90	−60.60	−67.41	5.72
H^3 (TU)	36	2.12	21.51	12.75	5.41
^14C (pmc)	3	13.60	16.80	15.53	1.70
δ ^13C-PDB (‰)	37	−13.98	−4.61	−9.95	2.19