Table 2.

Characteristic ionic solutes in the Uzon hydrothermal system (adapt from [8]).

Water Type	Chloride-Sodium Type			Sulfate Type			Bicarbonate Type
Components	mg/L	mg-eq/L	% mg-eq/L	mg/L	mg-eq/L	% mg-eq/L	mg/L	mg-eq/L	% mg-eq/L
pH	6.76			4.56			6.51
HCO₃⁻	12	0.2	0.3	< 0.6			654.1	10.72	70.7
Cl⁻	2234	63	96	2.1	0.06	12.8	29.1	0.82	5.4
SO₄^2-	96	2	3.1	19.2	0.4	85.1	172.9	3.6	23.8
F^-	1.2	0.06	0.1	0.2	0.01	2.1	0.2	0.01	0.1
Sum_an	2247.4	65.26	100	21.5	0.47	100	856.3	15.15	100
Na⁺	1307.4	56.87	89.5	6.4	0.28	56	164.7	7.16	45.9
K⁺	139.3	3.56	5.6	<0.39			11.6	0.3	1.9
NH₄⁺	3	0.17	0.3	0.1			< 0.1
Ca²⁺	52.9	2.64	4.2	3.2	0.16	32	92.2	4.6	29.5
Mg²⁺	2.9	0.24	0.4	0.7	0.06	12	43.2	3.55	22.7
Fe²⁺	< 0.3			< 0.3
Fe³⁺_com	< 0.3			< 0.3
H				0.1	0.07	0.8
Sum_cat	1505.5	6348	100	10.4	0.5	100	311.7	15.61	100
H₃BO₃	18.5			1.2			6.2
H₄SiO_4sol	190			48			182.6
H₄SiO_4col	452			77			11.3
Salinity	4413.4			158.4			1368.1

Analyses were made at the Analytical Center of the Institute of Volcanology and Seismology in Petropavlovsk by V.S. Sergeeva.