. 2018 Jan 17;4(1):eaao4842. doi: 10.1126/sciadv.aao4842

Table 1. Calculated fractions of ancient and modern C–sourced CH₄ in each sample.

Station	Water depth (m)	Distance offshore (km)	Sample type	Ancient C–sourced CH₄ fraction, f_s	Atmospheric-sourced CH₄ fraction, f_a	In situ produced CH₄ fraction, f_i
1	2	3	Lagoon	0.18 ± 0.06	0.47 ± 0.18	0.35 ± 0.25
2	3	2	Lagoon	0.50 ± 0.04	0.23 ± 0.12	0.27 ± 0.17
3	14	12	Surface	0.26 ± 0.06	0.37 ± 0.18	0.37 ± 0.24
3	14	12	Near-seafloor	0.60 ± 0.04	0.18 ± 0.10	0.22 ± 0.13
4	15	10	Surface	0.39 ± 0.05	0.29 ± 0.15	0.33 ± 0.20
4	15	10	Near-seafloor	0.45 ± 0.05	0.25 ± 0.14	0.30 ± 0.18
5	13	18	Surface	0.42 ± 0.05	0.27 ± 0.14	0.31 ± 0.19
5	13	18	Near-seafloor	0.58 ± 0.04	0.19 ± 0.10	0.23 ± 0.14
6	19	27	Surface	0.53 ± 0.04	0.21 ± 0.12	0.26 ± 0.16
6	19	27	Near-seafloor	0.83 ± 0.02	0.07 ± 0.04	0.10 ± 0.06
7	28	48	Surface	0.10 ± 0.03	0.72 ± 0.10	0.18 ± 0.13
7	28	48	Near-seafloor	0.86 ± 0.02	0.06 ± 0.04	0.08 ± 0.05
8	38	69	Surface	0.07 ± 0.03	0.79 ± 0.07	0.14 ± 0.10
8	38	69	Near-seafloor	0.61 ± 0.03	0.17 ± 0.10	0.22 ± 0.13

Table 1. Calculated fractions of ancient and modern C–sourced CH4 in each sample.