We
measure spontaneous imbibition of aqueous (deionized water and
KCl solutions of various concentrations) and oleic (kerosene and iso-octane)
phases in several dry organic shale samples selected from two wells
drilled in the Horn River basin. We find that the imbibition rate
of aqueous phases is much higher than that of oleic phases even when
plotted versus scaling dimensionless time, contrary to capillary-driven
imbibition models. The observed difference is more pronounced in samples
with higher clay content. The results suggest that the excess water
intake is due to (1) the additional driving force provided through
water adsorption by clay minerals, and (2) the enhancement of sample
permeability through adsorption-induced microfractures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.