Measurement of Cl⁻ : Br⁻ Ratios in the Porewater of Clay-Rich Rocks—A Comparison of the Crush-and-Leach and the Paper-Absorption Methods

Figure 2

Cl⁻ versus Br⁻ mass extracted using the paper-absorption and crush-and-leach methods for rock cores from the Michigan Basin, Opalinus Clay, and the Lorraine Group. Scaling factors of 10, 20, and 3.5, respectively, were applied to the masses extracted by crush and leach to allow for direct comparison between methods. A scaling factor of 50 was applied to the solute masses (L⁻¹) in the seepage water collected from boreholes in Opalinus Clay by Pearson et al. [29]. Error bars represent the instrumental error on solute analysis.