大庆油田萨零组粉砂岩储层敏感性研究

大庆油田粉砂岩储层呈现低孔、低渗的特征,容易受到敏感性的损害。对大庆油田粉砂岩储层按照敏感性评价标准进行了敏感性试验研究,结果表明:这类储层压力敏感性中等偏弱,围压对渗透率损害率43.2%,随围压降低渗透率恢复性好,恢复率从70%到95%。这类储层没有速敏性或很弱,盐敏性明显,程度中等偏弱,临界矿化度1800mg/L。水敏程度中等偏强,水敏指数56%。研究结果对油田的注水开发很有意义。

Study on sensitivity of siltstone reservoir of Saling formation in Daqing oilfield

The low-porosity and low-permeability siltstone res- ervoir in Daqing oilfield is subject to be damaged by sensitivi- ty.A study was performed to evaluate the sensibility of silt- stone reservoir,and results show that the pressure sensitivi- ty is moderate by weak.The damage ratio of confining pres- sure to permeability is 43.2%.With the better restoration of the confining pressure to reduce the permeability,the resto- ration ratio increases from 70%to 95%.At this kind of geo- logical setting,the reservoir has no or weak velocity sensi- tivity,but the salt sensitivity is apparent and the degree is medium to weak with the threshold salinity as 1800 mg/L, and the water sensitivity is in the medium by intense degree with the index as 56%.The study is of significance to the flood development.