Shale Wettability: Data Sets, Challenges, and Outlook

The wetting characteristics of shale rocks at representative subsurface conditions remain an area active debate. A precise characterization wettability is essential for enhanced oil and gas recovery, containment security during CO2 geo-storage, flow back efficiency hydraulic fracturing. While several methods were utilized in the literature to evaluate (e.g., contact angle measurements, spontaneous imbibition method ,and NMR method), we here review recently published data sets on measurements. objectives this are (a) develop a repository recent using measurements high pressure temperature (HPHT) conditions, (b) explore factors influencing wettability, (c) identify potential limitations associated with methods, (d) provide research outlook area. On basis reviewed here, conclude following: (1) Shale/oil/brine systems demonstrate water-wet strongly oil-wet behaviors. (2) Shale/CO2/brine usually weakly CO2-wet. (3) Shale/CH4/brine water-wet. key contributing that underpin variability include, but not limited to, operating total organic content (TOC), mineral matter, thermal maturity conditions. Thus, provides succinct analysis affords overview current state art technology possible future developments enhance understanding wettability.