The Scientific World Journal

Research Article

Hydrochemistry of the Hot Springs in Western Sichuan Province Related to the Wenchuan 8.0 Earthquake

Table 1

Physicochemical parameters of the 32 hot spring waters.


Number	Site	L (E)	(N)	Date	°C	TDS mg/L	K⁺ mg/L	Na⁺ mg/L	Ca²⁺ mg/L	Mg²⁺ mg/L	Cl⁻ mg/L	mg/L	mg/L	mg/L	ib %	δ ¹⁸O	δD	Chemical type

The LMSF zone
1	Sangzao Spring	104.35	31.61	11.06.2008	19.0	557.43	2.67	64.78	73.27	12.27	64.74	108.24	0.00	229.38	−0.01	−6.18	−61.66	CaNa–HCO₃SO₄
				01.11.2008	19.1	394.07	2.68	41.92	55.57	12.90	30.39	72.65	0.00	175.98	0.02	−9.79	−69.63	CaNa–HCO₃SO₄
				01.07.2009	19.7	367.75	2.60	40.26	50.64	12.04	30.57	71.52	0.00	158.27	0.02	−9.87	−68.40	CaNa–HCO₃SO₄
				22.04.2010	19.5	361.94	2.61	37.63	45.01	12.88	30.45	65.72	0.00	166.74	0.00	−9.96	−70.34	CaNa–HCO₃SO₄
2	Wenchuan Well	103.77	31.63	10.06.2008	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
				21.10.2008	15.4	1569.81	4.21	71.65	182.01	128.73	47.39	878.08	0.00	248.12	−0.01	−8.37	−72.01	MgCa–SO₄
				29.06.2009	15.5	1128.39	4.35	61.72	151.53	80.38	29.51	720.73	0.00	70.05	0.00	−10.14	−73.78	MgCa–SO₄
				20.04.2010	10.8	1033.14	4.55	54.99	137.22	70.43	30.47	687.83	0.00	46.65	−0.01	−10.02	−73.11	MgCa–SO₄
3	Lixian Well	103.59	31.48	09.06.2008	32.9	1579.54	5.64	35.95	252.78	103.76	8.15	862.32	0.00	310.70	0.00	−9.53	−80.88	CaMg–SO₄
				22.10.2008	29.5	1195.08	5.00	37.29	182.66	78.59	7.82	812.50	0.00	68.47	−0.01	−11.75	−81.76	CaMg–SO₄
				29.06.2009	27.1	1105.85	5.44	37.91	161.15	76.82	7.90	780.09	0.00	34.00	−0.01	−11.01	−82.13	CaMg–SO₄
				20.04.2010	29.5	1025.28	5.72	36.15	146.64	69.97	7.48	741.96	0.00	14.63	−0.02	−11.62	−80.88	CaMg–SO₄
4	Guergou Spring	103.17	31.46	11.06.2008	n.d.	349.33	2.33	91.11	5.24	0.80	2.58	21.76	0.00	223.52	0.00	−11.74	−116.81	Na–HCO₃
				21.10.2008	58.0	246.71	2.23	60.76	4.74	0.83	2.45	21.33	0.00	150.62	−0.01	−14.42	−116.49	Na–HCO₃
				28.06.2009	56.0	240.49	2.18	54.36	5.22	0.83	2.61	22.63	0.00	150.62	−0.03	−16.27	−116.99	Na–HCO₃
				19.04.2010	55.8	151.69	2.19	29.82	4.76	0.82	2.31	22.16	0.00	88.13	−0.05	−16.34	−116.65	Na–HCO₃
5	Jiuzhaigou Spring	103.00	31.52	11.06.2008	30.5	837.83	9.06	202.49	26.48	20.48	60.83	237.79	0.00	272.78	0.01	−14.01	−107.26	Na–HCO₃SO₄
				21.10.2008	32.1	813.62	9.15	189.00	26.01	20.66	64.16	225.51	0.00	272.34	0.01	−13.59	−106.10	Na–HCO₃SO₄
				28.06.2009	32.0	739.07	8.86	163.55	28.71	20.55	10.28	232.20	0.00	270.10	0.02	−14.57	−106.62	Na–HCO₃SO₄
				19.04.2010	27.3	728.04	8.75	150.98	26.73	20.41	9.65	241.18	0.00	267.84	0.00	−13.95	−106.54	Na–HCO₃SO₄

The MJF zone
6	Erdaohai Spring	103.32	32.73	08.06.2008	21.6	505.34	1.34	8.75	85.17	25.73	0.93	3.80	0.00	379.30	0.02	−13.72	−102.42	CaMg–HCO₃
				22.10.2008	20.7	511.71	1.32	8.80	84.02	25.05	0.98	4.08	0.00	386.99	0.01	−14.39	−102.46	CaMg–HCO₃
				29.06.2009	20.0	464.18	1.22	8.57	77.24	23.35	1.02	3.78	0.00	348.94	0.02	−14.57	−103.88	CaMg–HCO₃
				21.04.2010	19.8	428.70	1.27	8.21	76.73	23.23	0.97	3.56	0.00	313.61	0.04	−14.39	−103.29	CaMg–HCO₃
7	Kakagou Spring	103.68	32.98	08.06.2008	18.7	914.21	5.11	25.23	160.21	31.45	2.05	10.98	0.00	678.66	0.01	−13.56	−101.05	Ca–HCO₃
				23.10.2008	19.7	876.14	4.92	24.08	154.12	30.74	1.93	10.86	0.00	648.69	0.01	−13.37	−101.92	Ca–HCO₃
				30.06.2009	21.7	873.30	4.84	23.93	142.67	28.67	2.07	10.83	0.00	660.16	−0.01	−14.04	−100.46	Ca–HCO₃
				21.04.2010	19.7	815.42	4.79	23.55	134.00	31.65	1.84	10.33	0.00	608.89	0.01	−14.12	−101.80	Ca–HCO₃
8	Chuanpanqiao Spring	103.64	32.85	08.06.2008	8.8	1657.61	6.36	21.82	97.82	182.62	10.78	12.54	0.00	1324.27	−0.01	−14.20	−112.00	Mg–HCO₃
				23.10.2008	9.6	1598.09	6.52	21.88	103.64	183.57	10.56	12.72	0.00	1258.08	0.00	−14.30	−112.48	Mg–HCO₃
				30.06.2009	10.7	1557.18	5.89	21.68	103.79	175.29	10.55	11.54	0.00	1228.08	0.00	−15.34	−112.23	Mg–HCO₃
				21.04.2010	10.7	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	−14.95	−113.33	n.d.
9	Songpan Well	103.60	32.65	08.06.2008	9.0	647.31	1.64	14.05	55.71	65.01	2.34	17.78	0.00	490.23	0.01	−13.25	−101.54	MgCa–HCO₃
				23.10.2008	9.9	648.33	1.60	14.12	52.12	65.27	2.17	16.32	0.00	496.23	0.00	−13.43	−102.82	MgCa–HCO₃
				30.06.2009	9.3	610.38	1.57	13.93	49.54	65.43	2.25	16.24	0.00	461.42	0.02	−13.20	−102.20	MgCa–HCO₃
				21.04.2010	9.9	603.35	1.60	13.81	50.12	62.90	2.48	15.96	0.00	456.23	0.02	−13.77	−102.09	MgCa–HCO₃

The XSHF zone
10	Ganzi Well	100.00	31.62	12.06.2008	27.8	441.46	3.42	49.07	38.84	19.07	4.04	44.27	0.00	281.36	0.00	−15.93	−125.50	NaCa–HCO₃
				24.10.2008	29.8	447.22	3.53	47.97	37.51	19.97	3.94	43.44	0.00	289.54	−0.01	−16.48	−125.21	NaCa–HCO₃
				27.06.2009	29.6	416.83	3.43	47.91	37.39	19.13	4.06	43.34	0.00	260.25	0.01	−16.17	−125.79	NaCa–HCO₃
				18.04.2010	29.2	472.24	3.33	50.76	38.72	19.97	3.80	40.17	0.00	314.28	−0.01	−16.15	−125.75	NaCa–HCO₃
11	Ganzi Spring	100.00	31.61	12.06.2008	43.1	735.04	8.95	154.67	23.95	16.42	6.38	62.15	0.00	459.17	0.01	−16.33	−124.72	Na–HCO₃
				24.10.2008	41.5	731.75	9.08	150.20	23.13	16.34	6.19	60.61	0.00	461.22	0.00	−16.28	−124.30	Na–HCO₃
				27.06.2009	43.0	695.04	9.17	146.66	22.34	16.44	6.00	61.79	0.00	427.90	0.01	−16.45	−126.00	Na–HCO₃
				18.04.2010	41.4	706.99	9.29	138.30	21.87	16.42	6.17	63.67	0.00	447.27	−0.01	−16.29	−124.46	Na–HCO₃
12	Guyi Spring	100.80	31.27	13.06.2008	35.5	2218.75	12.68	607.07	11.30	21.81	6.09	12.25	142.80	1399.60	0.01	−16.38	−130.98	Na–HCO₃
				25.10.2008	31.3	2353.19	13.13	619.72	11.36	22.19	5.73	11.62	142.80	1524.39	0.00	−16.16	−131.17	Na–HCO₃
				26.06.2009	33.2	2239.88	12.63	593.59	10.33	21.82	6.11	11.60	157.21	1424.29	−0.01	−16.97	−132.52	Na–HCO₃
				18.04.2010	28.2	2366.42	12.63	619.91	10.01	21.31	5.95	12.35	108.56	1573.76	0.00	−16.56	−131.90	Na–HCO₃
13	Longpugou Spring 1	101.24	30.98	13.06.2008	37.8	1180.32	7.16	310.06	11.00	8.23	13.83	6.83	0.00	820.21	0.01	−16.74	−137.69	Na–HCO₃
				25.10.2008	37.2	1199.61	6.96	288.86	11.69	7.90	13.02	6.81	0.00	860.75	−0.01	−17.02	−136.73	Na–HCO₃
				26.06.2009	39.2	1164.18	6.90	280.27	11.28	7.80	13.27	6.61	0.00	836.33	−0.01	−17.41	−137.71	Na–HCO₃
				18.04.2010	36.5	1145.60	6.83	281.70	11.16	7.85	12.98	6.56	0.00	815.75	−0.01	−17.47	−138.90	Na–HCO₃
14	Longpugou Spring 2	101.24	30.95	13.06.2008	44.5	1070.89	6.47	221.80	18.30	26.65	8.85	10.09	57.10	719.87	−0.02	−16.85	−134.42	Na–HCO₃
				25.10.2008	42.5	927.46	6.93	205.03	18.90	26.11	8.28	9.78	0.00	650.41	0.02	−17.52	−134.80	Na–HCO₃
				26.06.2009	42.5	900.81	6.67	198.93	17.43	25.73	8.39	9.33	0.00	634.33	0.02	−16.63	−133.90	Na–HCO₃
				18.04.2010	43.2	919.25	6.48	176.77	18.84	25.93	8.53	9.63	0.00	671.47	−0.01	−17.61	−133.70	Na–HCO₃
15	Bamei Spring	101.62	30.54	14.06.2008	55.2	1966.85	76.60	443.00	15.17	29.06	23.77	6.78	0.00	1368.29	0.01	−17.34	−135.61	Na–HCO₃
				25.10.2008	55.6	1913.45	75.22	417.08	14.76	28.42	20.55	7.00	0.00	1346.62	0.00	−17.57	−134.51	Na–HCO₃
				26.06.2009	56.0	2068.93	77.29	463.31	14.32	26.66	20.58	6.81	0.00	1456.10	0.00	−17.54	−135.81	Na–HCO₃
				17.04.2010	55.6	2724.13	74.40	679.23	14.49	29.42	20.55	7.12	0.00	1894.64	0.02	−17.89	−134.41	Na–HCO₃
16	Guanding Spring	101.96	29.98	15.06.2008	80.5	1306.05	41.23	396.79	13.16	13.21	336.16	51.96	11.34	440.26	0.02	−14.24	−117.01	Na–ClHCO₃
				26.10.2008	80.0	1395.37	40.57	367.22	13.41	13.64	328.54	50.02	92.82	485.48	−0.03	−15.26	−118.02	Na–ClHCO₃
				25.06.2009	83.0	1353.81	42.72	367.40	13.67	13.50	320.93	49.72	99.82	443.09	−0.02	−17.02	−127.74	Na–ClHCO₃
				17.04.2010	83.0	1273.60	41.52	349.71	13.80	13.81	300.83	50.63	56.00	447.24	−0.01	−16.13	−123.72	Na–ClHCO₃
17	Longtougou Spring	101.96	29.98	15.06.2008	70.8	2044.87	53.20	510.82	16.02	31.42	220.68	8.33	0.00	1200.36	0.01	−15.99	−128.69	Na–HCO₃
				26.10.2008	70.2	2106.82	52.72	518.38	17.41	30.95	203.66	8.59	0.00	1270.92	0.00	−16.26	−127.78	Na–HCO₃
				25.06.2009	73.1	2025.87	52.27	516.68	16.71	30.84	226.15	8.30	0.00	1171.25	0.01	−16.61	−128.57	Na–HCO₃
				17.04.2010	70.2	2096.92	51.62	507.94	16.33	31.09	207.55	8.30	0.00	1270.92	0.00	−17.04	−130.94	Na–HCO₃
18	Zheduotang Spring	101.86	30.01	15.06.2008	54.5	681.59	3.13	208.79	4.87	0.12	10.55	17.57	67.83	342.06	−0.01	−18.06	−138.80	Na–HCO₃
				26.10.2008	53.8	705.52	3.14	219.83	4.38	0.12	10.57	17.31	85.68	338.08	−0.01	−18.21	−137.20	Na–HCO₃
				25.06.2009	53.4	650.33	3.04	207.09	4.44	0.12	9.59	16.57	35.89	346.59	0.01	−18.64	−141.98	Na–HCO₃
				17.04.2010	53.8	663.17	2.87	208.84	4.72	0.12	9.76	16.42	88.25	305.09	−0.02	−18.84	−139.88	Na–HCO₃
19	Erdaoqiao Spring	101.95	30.09	15.06.2008	39.1	843.39	23.54	150.53	22.10	44.05	43.88	114.59	0.00	443.52	0.02	−14.50	−112.90	NaMg–HCO₃
				26.10.2008	39.4	919.66	22.47	150.67	22.08	44.68	40.36	107.06	0.00	530.93	0.00	−14.54	−112.16	NaMg–HCO₃
				26.06.2009	40.6	926.35	22.36	146.31	20.20	44.48	43.92	109.47	0.00	538.41	−0.02	−15.57	−115.14	NaMg–HCO₃
				16.04.2010	40.6	935.65	23.67	157.07	20.93	43.76	40.97	111.59	0.00	535.44	0.00	−15.01	−115.35	NaMg–HCO₃
20	Xinxing Spring	102.06	29.75	16.06.2008	45.6	1287.50	9.41	422.66	12.53	9.69	148.03	28.85	106.33	545.15	0.03	−15.90	−115.30	Na–HCO₃
				27.10.2008	44.1	1167.77	9.68	365.04	12.75	9.43	144.03	24.65	0.00	597.19	0.05	−15.53	−115.83	Na–HCO₃
				24.06.2009	42.8	1289.88	9.23	360.63	11.97	9.36	148.41	24.07	124.73	597.17	−0.02	−15.63	−114.96	Na–HCO₃
				23.04.2010	48.2	1038.46	9.19	303.10	12.04	8.98	156.23	21.31	0.00	523.35	0.02	−15.21	−115.86	Na–HCO₃
21	Gonghe Spring	102.11	30.62	16.06.2008	48.8	578.15	9.94	108.43	19.30	22.06	18.44	60.27	0.00	337.54	0.01	−11.91	−88.74	Na–HCO₃
				27.10.2008	47.6	598.18	10.03	106.53	20.12	22.07	17.83	60.07	0.00	359.48	0.00	−12.40	−90.07	Na–HCO₃
				24.06.2009	50.0	610.23	9.57	107.62	18.49	21.27	17.36	65.08	0.00	368.95	−0.01	−12.49	−89.29	Na–HCO₃
				23.04.2010	44.8	585.91	9.41	111.76	19.32	21.47	17.85	64.11	0.00	339.32	0.01	−12.33	−89.00	Na–HCO₃
22	Erhaoying Spring	102.03	29.59	17.06.2008	65.5	597.31	18.34	154.11	13.45	4.62	37.14	59.30	0.00	307.61	0.02	−14.22	−105.92	Na–HCO₃
				27.10.2008	67.4	645.11	18.25	156.50	13.48	4.64	36.80	62.21	0.00	349.86	0.00	−14.31	−109.95	Na–HCO₃
				25.06.2009	63.0	585.59	18.53	153.02	13.20	4.72	35.31	62.43	0.00	295.11	0.03	−15.13	−108.27	Na–HCO₃
				24.04.2010	67.4	631.67	18.29	150.44	13.01	4.75	35.97	59.85	0.00	348.99	0.00	−15.27	−108.87	Na–HCO₃
23	Tianwanhe Spring	102.14	29.49	17.06.2008	53.0	613.88	17.60	76.93	13.10	45.32	24.61	152.25	0.00	281.49	−0.01	−10.31	−79.22	NaMg–HCO₃SO₄
				25.10.2009	n.d.	632.23	16.92	73.37	12.74	45.71	23.42	139.62	0.00	317.73	−0.02	−10.04	−78.77	NaMg–HCO₃SO₄
				24.06.2009	54.0	611.73	17.58	79.12	12.81	43.62	24.91	145.24	0.00	286.45	−0.01	−10.50	−83.14	NaMg–HCO₃SO₄
				24.04.2010	53.2	644.79	17.44	79.11	12.71	44.44	25.65	145.44	0.00	317.73	−0.02	−10.59	−80.38	NaMg–HCO₃SO₄
24	Caoke Spring	102.10	29.39	18.06.2008	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
				28.10.2008	41.4	407.78	3.00	48.74	50.10	6.19	3.97	155.60	0.00	139.19	−0.02	−12.38	−88.30	CaNa–SO₄HCO₃
				24.06.2009	42.9	363.08	2.97	46.19	44.43	6.11	3.94	160.52	0.00	98.05	−0.01	−12.50	−91.09	CaNa–SO₄HCO₃
				24.04.2010	41.4	369.36	3.03	46.29	45.63	6.17	3.57	161.87	0.00	101.89	−0.02	−12.59	−90.94	CaNa–SO₄HCO₃
25	Shimian Well	102.22	29.44	18.06.2008	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
				28.10.2008	30.4	150.26	2.35	38.60	6.99	1.20	2.58	17.82	0.00	69.62	0.00	−11.08	−87.15	Na–HCO₃
				23.06.2009	31.3	149.10	2.39	37.61	6.46	1.23	2.44	17.29	0.00	70.79	0.00	−11.28	−90.21	Na–HCO₃
				24.04.2010	31.2	137.77	2.34	35.14	6.86	1.20	2.35	17.16	0.00	62.48	0.01	−10.51	−88.94	Na–HCO₃

The ANHF zone
26	Gongyihai Spring	102.39	29.02	18.06.2008	56.9	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	−14.23	−108.54	n.d.
				28.10.2008	54.1	320.27	3.34	109.14	2.37	1.00	1.91	46.17	0.00	82.11	0.00	−14.19	−108.67	Na–HCO₃SO₄
				23.06.2009	55.4	306.82	3.37	100.47	2.40	1.01	1.99	48.14	0.00	81.95	−0.01	−14.83	−110.47	Na–HCO₃SO₄
				24.04.2010	56.4	323.92	3.23	113.91	2.44	1.02	3.80	47.98	0.00	88.81	0.02	−14.82	−110.20	Na–HCO₃SO₄
27	Chuanxin Spring	102.36	28.26	19.06.2008	n.d.	462.71	4.80	86.08	15.24	11.55	5.52	12.67	0.00	325.96	−0.01	−13.46	−106.54	Na–HCO₃
				28.10.2008	n.d.	449.48	4.25	86.72	15.29	11.45	5.18	12.44	0.00	311.73	0.45	−13.32	−106.98	Na–HCO₃
				23.06.2009	49.0	483.93	4.23	85.56	13.75	10.18	4.66	12.00	0.00	351.73	−0.04	−14.51	−108.29	Na–HCO₃
				24.04.2010	45.1	456.34	4.23	85.46	13.21	9.52	4.72	12.74	0.00	325.14	−0.02	−13.41	−107.37	Na–HCO₃
28	Taihe Spring	102.14	27.91	19.06.2008	21.1	226.41	0.69	58.65	4.03	0.76	1.99	12.76	0.00	146.70	0.01	−13.37	−106.65	Na–HCO₃
				29.10.2008	21.1	206.70	0.66	53.56	4.02	0.00	1.91	12.72	0.00	132.20	0.00	−13.31	−106.32	Na–HCO₃
				n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
				n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
29	Xichang Well	102.15	27.91	19.06.2008	22.3	261.87	0.31	78.93	2.08	0.81	21.78	15.22	0.00	137.09	0.01	−13.78	−106.89	Na–HCO₃
				29.10.2008	n.d.	229.28	0.32	71.76	2.15	0.85	21.32	15.22	0.00	112.05	0.02	−13.23	−106.64	Na–HCO₃
				22.06.2009	24.2	238.13	0.33	69.68	2.00	0.81	21.38	15.65	0.00	123.05	0.00	−13.24	−106.07	Na–HCO₃
				n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
30	Zhuhexiang Spring	102.93	28.07	19.06.2008	49.8	256.45	4.65	54.62	13.18	2.42	3.99	11.97	0.00	161.91	0.02	−12.62	−100.01	Na–HCO₃
				29.10.2008	49.7	248.22	4.57	51.93	13.39	2.35	3.91	12.22	0.00	154.30	0.00	−12.67	−100.50	Na–HCO₃
				22.06.2009	49.8	244.72	4.27	50.23	13.75	2.36	3.96	12.05	0.00	152.89	0.00	−13.53	−99.12	Na–HCO₃
				26.04.2010	48.0	255.93	4.27	50.17	13.26	2.44	3.80	12.31	0.00	167.97	0.00	−12.86	−100.54	Na–HCO₃
31	Lizhouzhen Spring	102.24	28.09	19.06.2008	n.d.	331.37	14.12	54.16	30.00	0.00	5.52	11.33	0.00	212.12	0.01	−14.48	−110.35	NaCa–HCO₃
				29.10.2008	48.1	326.67	14.66	52.79	30.77	0.00	5.38	11.34	0.00	210.92	0.02	−14.71	−110.23	NaCa–HCO₃
				22.06.2009	49.0	323.38	13.37	48.45	29.36	0.00	6.14	10.93	0.00	210.00	−0.01	−14.11	−110.74	NaCa–HCO₃
				25.04.2010	48.6	321.73	14.08	49.49	29.49	0.00	5.45	11.06	0.00	209.92	0.00	−14.63	−110.06	NaCa–HCO₃
32	Luojishan Spring	102.54	27.40	20.06.2008	n.d.	1212.86	49.31	208.79	81.48	29.43	136.74	257.26	0.00	449.06	0.00	−11.76	−96.43	Na–HCO₃SO₄
				29.10.2008	43.7	1172.03	46.80	213.50	81.42	28.43	135.47	255.58	0.00	407.06	0.01	−11.64	−96.10	Na–HCO₃SO₄
				22.06.2009	43.8	1150.63	46.67	213.09	71.12	26.07	135.76	244.07	0.00	412.82	0.01	−13.41	−96.20	Na–HCO₃SO₄
				25.04.2010	43.8	1127.84	43.86	200.41	73.26	26.02	135.37	252.58	0.00	395.58	0.00	−13.18	−96.77	Na–HCO₃SO₄

The “n.d.” represents samples not analysed.