TABLE 2.
Normalized hydrocarbon concentrations and isotope properties of gasses from gas hydrate samples
| Sample | % Methane concn (δ13C)a | δD Methaneb | % Ethane concn (δ13C) | % Propane concn (δ13C) | % Isobutane concn (δ13C) | % n-Butane concn (δ13C) | % Isopentane concn (δ13C) | % n-Pentane concn (δ13C) | CO2 δ13C |
|---|---|---|---|---|---|---|---|---|---|
| MC853 | 75.3 (−45.1) | −166 | 6.8 (−28.4) | 11.3 (−24.5) | 3.4 (−27.0) | 0.7 (−23.4) | 0.3 (ND)c | <0.1 (ND) | +11.6 |
| AT425 | 77.3 (−49.3) | −148 | 5.0 (−38.2) | 12.5 (−32.0) | 3.0 (−31.6) | 1.2 (−28.3) | 0.9 (−28.8) | 0.2 (−28.4) | +12.4 |
| KC695 | 99.9 (−70.1) | ND | 0.1 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | ND |
| AT98 | 99.9 (−74.7) | −155 | 0.1 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | 0 (ND) | ND |
| GC185 | 84.1 (ND) | ND | 5.5 (ND) | 5.7 (ND) | 1.7 (ND) | 0.8 (ND) | 2.2 (ND) | 0 (ND) | ND |
a
δ13C values are reported in parts per thousand relative to the Peedee Belemnite standard.
b
δD values are reported in parts per thousand relative to the SMOW standard.
c
ND, no data.