EVALUATING THE WETTABILITY OF DIFFERENT RESERVOIR ROCKS BY SPONTANEOUS IMBIBITION

Wettability, which is an important parameter controlling hydrocarbon production, is determined by the combination of all forces at the interface between solids and liquids or gases. One type of reservoir rock may have different affinity to different fluids (oil, gas, or water), which could lead to different interfacial tensions and contact angles between the fluid and solid. Spontaneous imbibition is one of the important processes during oil/gas recovery and its rate depends on the wettability and the pore structure of the porous media. As a result, the spontaneous imbibition experiment could be used to evaluate the wettability of porous media. Using different liquids (including water and decane) as the imbibing phase to conduct the imbibition experiments on the same sample, we’ve performed imbibition experiments on several types of reservoir rocks (sandstone, chalk and shale). Rock wettability is assessed from the imbibition data by the theoretical work available in the literature .