Table 5.

Abundances of Principal Constituents in Hydrothermal Vent Fluxes (Tivey, 2007), Compared with Abundances Calculated by Our Model

	Mid-ocean ridge		Back-arc basin		Rainbow		Lost City
	Observed	Our model	Observed	Our model	Observed	Our model	Observed	Our model
T (°C)	≤405	405	278–334	306	365	365	≤91	91
H2 (mol m−3)	5×10−4 to 38	1.3×10−2	0.035–0.5	460	13	8.1	<1–15	1×10−7
CO2 (mol m−3)	3.56–39.9	16.1	14.4–200	1.8×10−8	—	1.9×10−8	—	18.2
CH4 (mol m−3)	7×10−3 to 2.58	2.56	5×10− 10−2	18.8	0.13–2.2	18.7	1–2	0.5