Biogenic CH4 (‰) | Thermogenic CH4 (‰) | Pyrogenic CH4 (‰) |
δ13C-CH4: −110 to −50 δ2H-CH4: −275 to −100 | δ13C-CH4: −50 to −20 δ2H-CH4: −275 to −100 | δ13C-CH4: −25 to −13 |
[11] [12] [13] | [11] [13] | [14] [15] |