TABLE 1.

Geochemistry of Happo #3 from 2011 to 2016.

	2011a	2016
Temperature	48°C	47.5°Cb
pH	10.7	10.95b
ORP	n.m.	−435 mVb
EC	48.3 mS/m	47.7 mS/mb
DO	0.59 mg/L	0.10 mg/Lb
Salinity	0.02%	n.d.b (detection limit 0.1%)
H2	201 μM	n.m.
CH4	124 μM	n.m.
C2H6	0.2 μM	n.m.
N2	1298 μM	n.m.
Ca2+	130 μM	220 μM
K+	70 μM	125 μM
Na+	1160 μM	1565 μM
NH3	n.m.	7 μM
Al3+	10 μM	n.m.
Li+	10 μM	n.m.
Cl–	180 μM	155 μM
SO42–	10 μM	8 μM
F–	4 μM	n.m.
Formate	n.m.	80 μM
Acetate	n.m.	<40 μM
Not detectedc		Pyruvate, lactate propionate, NO2–, NO3–, HCO3–, Mg2+, PO42–, total Fe, nucleobases, nucleosides, and amino acids

^aPublished in Suda et al. (2014). ^bNobu et al., unpublished data. ^cNo peak detected; Detection limits: Pyruvate (40 μM), lactate (40 μM), propionate (40 μM), NO₂^– (2.2 μM), NO₃^– (1.6 μM), HCO₃^– (0.02 μM), Mg²⁺ (20.6 μM), PO₄^2– (0.01 μM). CO₂ and total Fe not detected as described in Suda et al. (2014). Nucleobases and nucleosides include cytosine (179 nM), uracil (659 nM), adenine (740 nM), guanine (1.3 μM), C-ribonucleosides (47 nM), U-ribonucleosides (340 nM), A deoxyribonucleosides (71 nM), G deoxyribonucleosides 64 nM), C-deoxyribonucleosides (470 nM), T-deoxyribonucleosides (133 nM), A-deoxyribonucleosides (400 nM), and CH1 amino acids (50 μM). n.m. = not measured. n.d. = not detected.