Improvements in Drill-Core Headspace Gas Analysis for Samples from Microbially Active Depths

<div>Temporal variations in (a) <i>δ</i><sup>13</sup>C<sub>CO2</sub> and (b) <i>δ</i><sup>13</sup>C<sub>CH4</sub> after sampling. Solid arrow indicates the trend for samples with 350 m groundwater; dashed arrow indicates the trend for samples with 50 m groundwater.</div>

Geofluids

fig4

Figure 4

Figure 4: Improvements in Drill-Core Headspace Gas Analysis for Samples from Microbially Active Depths 