Effect of Surface Preparation on Sessile Drop Contact Angle Results on Shale Surfaces

Abstract

Sessile drop contact angle measurements are a common wettability measurement of low permeability shale surfaces but contact angle measurements are influenced by the surface preparation methods. This thesis demonstrates how various preparation methodologies can generate differing results. Green River Shale, Lower Eagle Ford Shale, and Tuscaloosa Marine Shale samples were evaluated using aluminum oxide, silicon carbide, and diamond abrasives using dry and wet polishing methods to observe the effect of water interacting with the surface through the measurement of contact angles. A method of accurately measuring the apparent static contact angle of the permeable surfaces is proposed using a pseudo-stabilized measurement point methodology to identify the Young’s contact angle when the droplet volume is constantly changing. Understanding the effects of surface preparation is required to create a standardized method of shale surface preparation which will increase the accuracy and precision of contact angle measurements.