Figure 3
Geology (Site 5) and dissolved CH4 concentrations (a), Cl− concentrations (b), and δ13C-CH4 values (c) vs. depth below the top of the Pierre Shale at Site 5. Site 6 data from Fig. 2 are added in this figure to show the different CH4 and Cl− profiles at Site 5 versus Sites 2 and 6. The Isojar® data from Site 5 are shown as solid red dots, and mud gas data from Sites 5 and 6 as solid green squares and solid blue triangles, respectively.
