Conventional methods for wettability determination of shales: A comprehensive review of challenges, lessons learned, and way forward

The wettability is a critical property that governs the in situ fluid distribution, fractional flow, and hydrocarbon trapping porous media. This topic of immense interest to petroleum industry for exploitation unconventional resources, which have become significant source oil gas production, especially North America, Canada, China, as result advancement horizontal drilling fracking technologies. conventional techniques central focus determination shales include contact angle, spontaneous imbibition, flotation. paper reviews published literature analyzes challenges lessons learned from each method applicable shales. results various are compared, their consistency highlighted. Comparative angle measurements can characterize surficial hysteresis dynamic processes Spontaneous imbibition recommended most realistic representative measurement method, whereas it reveals pore connectivity internal network. However, different liquid/rock interactions, mainly clay swelling creation micro-fractures, affect thus necessitate application reservoir triaxial stress conditions on shale samples. In this review, finally, some concluding remarks recommendations presented.