Groundwater Chemistry and Overpressure Evidences in Cerro Prieto Geothermal Field

Table 1

Major elements concentration values at CP groundwater samples measured in summer 2010.

Well	Operation areas (individual units)	Depth		pH	C E	TSD	Ca	Mg	Na	K		Cl^-		% IB	B	SiO2
		(Km)	(°C)		mS/cm	Calculated	(mg/L)	(mg/L)	(mg/L)	(mg/L)	(mg/L)	(mg/L)	(mg/L)		(mg/L)	(mg/L)
M 104	CP3	1.73	88.4	7.73	20.45	20613.2	261.6	50.9	6250	1187.5	41.5	11962.5	13.5		13.26	851.7
M 117A	CP3	2.89	91.2	7.7	35	17315.5	140.2	34.7	5575	1185	18.4	9375	0.09		14.65	980.1
M 119A	CP2	3.1	87.9	6.79	35	34506.9	379.1	38.3	9850	2682.5	10.7	20150	0.09		17.42	1401.7
M 127	CP2	2.5	76.8	7.61	24.8	21457.8	288.3	31.1	6087.5	1352.5	28.4	12812.5	5.9		18.4	847.4
M 133A	CP3	2.49	80.8	7.49	35.45	36545.4	819.4	53.9	10750	1840	19	22200	14.2		19.86	853.9
M 148A	CP2	2.99	85.8	7.43	26.8	27327.2	379.1	28.7	8300	1652.5	21.3	15875	7.1		18.45	1074.3
M 155	CP3	2.9	80.5	7.44	36.65	38863.8	735.5	44.9	11325	2050	27.2	23800	0.09		27.92	890.2
M 198	CP4	2.8	91.8	7.52	21.85	25601.2	187.6	56.9	7587.5	1577.5	16.6	15250	0.09		28.8	915.9
M 200	CP3	2.84	82.8	7.42	25.85	22151.3	183.6	25.1	6312.5	1690	28.4	12950	0.09		22.35	973.7
112	CP1	2.65	86	7.25	33.05	31216.4	533.1	47.9	9125	1992.5	14.8	18250	0.09		15.8	1260.5
233	CP2	2.64	88.9	7.53	4.34	23971.6	189.5	29.9	7275	1490	23.7	13700	3.6		16.6	1262.6
311	CP3	2.94	85.1	7.56	43	23548.8	288.3	23.9	7137.5	1432.5	11.8	13550	5.4		21.9	1091.4
323	CP3	2.9	94.6	7.67	26.75	27018.9	286.3	53.9	7437.5	1482.5	37.9	16750	0.09		22	973.7
343	CP3	2	95.8	7.48	28.5	34309.7	789.8	59.9	9712.5	1447.5	14.3	21587	29		17.56	667.7
403	CP4	2.89	82.8	7.32	16.1	15503	167.8	59.9	4540	1030	42.6	8950	4.4		28.85	727.6
407	CP4	2.99	88.4	7.91	18.95	20042.6	108.6	35.9	5815	1185	19	11887.5	8.5		16.7	969.4
611	CP3	2.52	88.4	7.87	52.85	33262.9	730.5	53.9	9875	1585	19	20100	22.4		21.61	877.4
222 D	CP2	3.14	92.2	7.74	29.75	28719.9	296.2	27.5	8062.5	1907	9.5	17300	0.09		11.25	1114.9
E-23	CP2	2.95	71.1		58.5	39344.1	580.5	21.6	11175	2717.5	28.4	23750	0.09		24.2	1080.7
E-29	CP2	2.69	83.3	7.12	79.4	44491.3	785.8	14.4	13200	2962.5	21.3	26600	0.09		26.55	918
E-47A	CP3	2.89	91.7	7.47	61	35074.6	647.6	16.8	10650	2247.5	16.6	20500	0.09		21.97	995.1
T 350A	CP2	2.9	82	6.88	82.2	49251.2	1032.6	22.8	14312.5	2782.5	15.4	29700	0.09		28.55	1393.1
T 395	CP2	2.65	80.1	7.92	4.88	23924.2	337.6	27.5	7037.5	1420	4.7	14062.5	6.3		10.25	1016.5
T 400	CP1	2.1	89.6	7.9	19.73	12945.5	122.4	33.5	3910	560.5	20.7	7570	33.6		9.11	680.5
611A	CP3	2.52	87.6	7.85	52.4	33217.5	704.9	37.1	10087.5	1595	20.1	19875	22.5		22	877.4