ALKALI METAL SILICIDES FOR HIGH TEMPERATURE WETTABILITY IMPROVEMENT IN CARBONATE RESERVOIRS
A process for altering a wettability characteristic of a carbonate formation to stimulate oil production includes selecting an oil bearing carbonate formation, injecting a silicide dispersion into the carbonate formation, and reacting the injected silicide dispersion with water. The reaction alters the wettability characteristic of the carbonate formation toward water wettability. The silicide dispersion can include an alkali metal silicide, such as sodium silicide. The reaction generates hydrogen, silicate, and heat that pressurizes the carbonate formation with the generated hydrogen, heats the carbonate formation with the generated heat, and reduces the viscosity of the hydrocarbons in the carbonate formation with the generated silicate. The reaction re-mineralizes the surfaces in the carbonate formation and alters the wettability characteristics of the carbonate formation as a calcium-silicon phase is formed. The hydrocarbons are recovered from the carbonate formation with a production well.