Chemical and Isotopic Compositions of Hydrothermal Fluids at Snail, Archaean, Pika, and Urashima Sites in the Southern Mariana Trough

Table 45.2 End-member compositions of volatile components in the hydrothermal fluids for all the sites in the Southern Mariana Trough in this study

Site	T_max	H₂S (μM)	ΔH₂S (μM)	O₂ (μM)	N₂ (μM)	CO₂ (mM)	ΔCO₂ (mM)	CH₄ (μM)	ΔCH₄ (μM)	H₂ (μM)	He (μM)	ΔHe (μM)	δ¹³C(CO₂) (‰VPDB)	Δδ¹³C(CO₂) (‰VPDB)	δ¹³C(CH₄) (‰VPDB)	δD(H₂) (‰VSMOW)	δD(CH₄) (‰VSMOW)	³He/⁴He (R_A)	Δ³He/⁴He(R_A)
Snail	116			N.D.	N.D.	78.8	±12.4	29.6	±5.1	N.D.	N.D.	N.D.	−1.33	±0.10	N.D.	N.D.	N.D.	8.15	±0.09
Archaean	343			N.D.	N.D.	N.D.	N.D.	N.D.	N.D.	N.D.	2.10		−2.00	±0.61	N.D.	N.D.	N.D.	8.37	±0.03
2004
2005–2010
Pika	330			N.D.	N.D.	33.7	±0.6	7.2	±0.2	N.D.	1.83	±0.08	0.14	±0.06	N.D.	N.D.	N.D.	8.27	±0.10
2005						69.1	±2.1	29.9	±2.0
Urashima	280	883	±43	N.D.	N.D.	23.2	±0.4	10.8	±0.3	N.D.	2.40	±0.1	−2.36	±0.17	N.D.	N.D.	N.D.	8.09	±0.19