Wettability is a tendency of fluid to stick to the surface of formation when other types of fluid are present. Wettability of rock is measured by a core analysis in a laboratory and typically a laboratory measure contact angle between the fluid and the rock.
Wettability of rock is classified by the angle of contact, which is divided into 3 categories.
Water wet – contact angle (θ) is less than 90 degrees
Figure 1 – Water Wet Continue reading