根据水膜稳定性研究储层润湿性

鉴于常规储层润湿性研究方法在低渗或特低渗透储层中应用的局限性,提出了根据储层表面水膜稳定性来研究储层润湿性的方法。根据原油、地层水和成岩矿物的物性参数、矿物表面曲率以及毛管压力,用DLVO理论和推广的Young-Laplace公式可以计算岩石表面水膜的分离压力,其大小表征了岩石表面水膜的稳定性,以此判定储层的润湿性。应用该方法测定了加拿大高沥青质含量的Athabasca储层和大庆外围低渗透储层的润湿性,均为亲水润湿性,与储层实际相一致,为在分子水平上研究储层岩石的均质和各种复杂的非均质润湿性开辟了一条新的途径。

STUDY OF RESERVOIR WETTABILITY THROUGH WATER FILM STABILITY

Due to limitations of routine reservoir wettability measurements in low or very low permeability reservoirs,a new method based on stability of water film over rock surface has been suggested.According to physical properties of crude oil,strata water and minerals,with the DLVO theory and the promoted Young-Laplace formula,disjoining pressure of water film over rock surface can be calculated,which stands for stability of water film,hence can be used to judge wettability.Wettability of Athabasca reservoir with high bitumen content in Canada and low permeability reservoir around Daqing Oil Field has been measured,both water-wet.This measurement opens a new way for studies of homogeneous and all kinds of complex heterogeneous wettability of reservoir in the molecular level.