Table 1 Concentrations and isotopic compositions of known carbon species in the Lost City environment. n.d. is not determined.

CH₄^13,21

890–1980

−13.6 to −9.3

0.002 to 0.006

C₂H₆ - C₄H₁₀¹³

0–1.8

−16.9 to −13.1

n.d.

Formate^{14 ,present work}

36–158

−12.1 to −6.8

0.09 to 0.56

Acetate^{14 ,present work}

1–35

−26.6 to −20.3

n.d.

Total hydrolizable amino acids⁶⁷

0.7–2.3

n.d.

n.d.

Mantle CO₂ ‘predicted’ to be in endmemeber fluids^a

2000–4100

−12 to −2

0

Dissolved ΣCO₂ in endmemeber fluids from Mkrs C, 2, B¹³

0.1–1 (avg 0.2)

≈ −9

n.d.

Dissolved ΣCO₂ in endmemeber fluids from Mkr 3¹³

10–26

≈ −9

n.d.

Dissolved inorganic carbon in seawater (800 & 550 m)¹³

2200

0.8

0.993 to 1.052

Calcium Carbonate^21,23

n/a

−7 to + 13

0.957 to 1.002

Total organic carbon^21,53

400–1500 ppm

−12.4 to −3

0.480 to 0.888

Total hydrolizable amino acids⁶⁷

n.d.

−18.3 to + 8.7

n.d.

Bacterial lipids (fatty acids, non-isoprenoidal diethers)^37,42

0–2.4 µg lipid/g chimney

−31 to −1.1

n.d.

Archaeal lipids (isoprenoidal diethers, PMIs)^37,42

0–3.5 µg lipid/g chimney

−12 to + 24.6

n.d.

Eukaryotic lipids (polycyclic terpanoids)^37,42

0–0.5 µg lipid/g chimney

−28.5 to −15.4

n.d.

Mono-unsaturated fatty acids, >95% C16:1 and C18:1^b

−18.7

0.68 ± 0.03

Saturated, straight-chain fatty acids, >99% C16:0^b

−8.9

0.13 ± 0.02

Combined Pentamethylicosanes^b,c

1.7

0.24 to 0.49

Squalene^b

−11.0

0.17 ± 0.02

Phytanic Acid^b

−1.4

0.22 ± 0.02