不同黏土矿物胶结的低渗透储层渗透率应力敏感性对比——以鄂尔多斯盆地延长组储层样品为例

通过应力敏感性实验,研究鄂尔多斯盆地延长组富含绿泥石和富含高岭石的低渗透砂岩储层的渗透率应力敏感性。结果表明,富含绿泥石储层的渗透率应力敏感性较弱,而富含高岭石储层的渗透率应力敏感性较强;富含绿泥石的不同岩样,随着初始渗透率减小,应力敏感性显著增强,而富含高岭石砂岩的渗透率应力敏感性与初始渗透率大小的相关性较差,这与高岭石的生长模式有关。因此,富含高岭石的低渗透砂岩油藏的开发应采用超前注水技术,尽可能地保持地层压力,降低开发过程中渗透率应力敏感性对产能的不利影响。

Contrast of stress sensitivity of low permeability reservoir with different clay minerals

Through the stress sensitivity experiment,the study of permeability stress sensitivity of low permeability sandstone reservoir from Yanchang formation in Ordos basin was carried out.The results indicated the reservoir rich in chlorite had weak stress sensitivity,while the reservoir rich in kaolinite had strong permeability.With the reduction of different initial permeability,chlorite had remarkable increase of stress sensitivity,while kaolinite sandstone had poor correlation with the initial permeability,which was associated with the growth pattern of kaolinite.Therefore,in the development of low permeability sandstone reservoir rich in kaolinite,advanced water injection technology should be adopted,with maintained formation pressure as far as possible,so as to lower the adverse effect of the stress sensitivity to permeability.