辽河油田东部凹陷火成岩储层孔隙结构评价

Pore structure evaluation for igneous rock reservoirs in eastern depression of Liaohe Oilfield

对火成岩储层的核磁共振测井资料和实验室压汞资料进行对比,采用插值法建立地层孔隙流体的横向弛豫时间T_2与压汞曲线的压力P_C之间的关系,发现它们之间满足对数关系,并用T_2谱构造毛管压力曲线。分别利用线性方法和对数方法构造毛管压力曲线,对数方法构造的毛管压力曲线与实验测量的毛管压力曲线更接近。将研究结果应用于辽河油田东部凹陷火成岩储层孔隙结构的评价中,发现分选系数小、孔喉歪度大、最大进汞饱和度高和平均孔喉半径大的毛管应力曲线对应的孔隙结构较好。

Through the comparison of NMR logging data with laboratory pressure mercury data of igneous rock reservoirs,the relationship between transverse relaxation time T2 and pressure PCof the formation pore fluid is established by using interpolation method,which is logarithmic relationship.According to this relationship,the authors use T2 spectrum to construct capillary pressure curves.Linear method and logarithmic method are used to construct capillary pressure curves,and the capillary pressure curve by logarithmic method is closer to the experimental capillary pressure curve.The application of research results in the study of igneous rocks in eastern depression of Liaohe Oilfield has a good effect in evaluating pore structure of igneous rock reservoirs.The study found that a capillary stress curve with small sorting coefficient,large pore throat slanting degrees,high value maximum into mercury saturation and big average pore throat radius has better corresponding pore structure.