Organic-rich mudrock wettability has been reported in the literature has a wide spectrum from water-wet to mixed-wet and oil-wet. Conventional methods for characterizing the wettability (e.g. Amott, USBM wettability indices) are challenging in tight rocks such as organic-rich mudrocks due to their extremely low permeability, porosity and complex pore structure. Moreover, forced imbibition on tight shale rocks requires significant pressure drop which could lead to induced fractures. Spontaneous imbibition and contact angle measurements has therefore been widely used to quantify wettability of shales . Studies on imbibition of liquid on crushed shale packs have been used to determine the wettability of the shales (Lan et al. 2015; Rezaee 2015). Spontaneous imbibition is primarily impacted by the wettability of rock components. Floatation technique is another technique to determine wettability of mudrock samples quantitatively . In this technique granulated sample of the organic-rich mudrock is placed inside a separating funnel with equal proportions of water and oil. The funnel is then shaken thoroughly and the particles are allowed to settle. The distribution of particles in the oil and water phases provides a measure of hydrophobicity of shale.