Wettability is a fundamental property of the interactions between the reservoir rock components and the pore filling fluids. Wettability is a controlling factor on the location of the reservoir fluids within its porous structure and upon the flow and subsequent distribution of fluids during the dynamic process of production. It is therefore an essential factor during laboratory experimentation, since it will have a controlling influence on all laboratory tests attempting to imitate reservoir characteristics and processes, especially capillary pressure and relative permeability.
There are a number of methods for quantitatively determining the wettability of the rock/fluid system:
- Contact angle;
- Amott method (often called Amott–Harvey);
- U.S. Bureau of Mines (USBM Centrifuge method);
- Spontaneous Imbibition and Drainage;