Figure 15: Marcellus Shale samples in spontaneous imbibition cells after treated in different HCl solutions: A) Marcellus sample cut parallel to bedding after 1wt.% HCl treatment B) Marcellus sample cut parallel to bedding after 2 wt.% HCl treatment C) Marcellus sample cut perpendicular to bedding after 2 wt.% HCl treatment.