Fluid	Seawater endmember	Unit	Notes	Finn hydrothermal fluid	Unit	Notes
	pH	8.15			5
	Temperature	2	˚C		298	˚C
	TDS	35000	mg/kg		40000	mg/kg	calculated
	O2 (aq)	4	mg/kg		1.00E-40	molal	PPM buffer
	HCO3-	0.0024	molal		0.6	meq/l
	H2S	–			2.1	mmolal	free
	SO4-2	28	mmolal		–
	NH4+	–			200	µmolal
	NO3-	1	mg/kg		–
	Cl-	560	mmolal		660	mmolal
	Na+	480	mmolal		513	mmolal
	K+	10	mmolal		38	mmolal
	Mg+2	54	mmolal		9.4	mmolal
	Ca+2	10	mmolal		52.2	mmolal
	SiO2 (aq)	5.3	mg/kg		12.5	mmolal
	Fe+2	2	µg/kg		78	µmolar
	Mn+2	0.2	µg/kg		136	µmolar
	Zn+2	2	µg/kg		24.4	µmolar
	Al+3	2	µg/kg		24.7	µmolar
	Cu+	0.5	µg/kg		3.5	µmolar
	Li+	180	µg/kg		490	µmolal
	Ni+2	0.5	µg/kg		0.93	µmolar