姬塬油田长6储层可动流体赋存特征及渗流能力分析

Characteristics of movable fluids saturation and research on seepage ability in Chang 6 reservoir in Jiyuan oilfield

以鄂尔多斯盆地姬塬油田长6段低渗透砂岩储层为研究对象,应用核磁共振、铸体薄片、扫描电镜、油水相渗等实验测试资料,对姬塬油田长6储层可动流体的赋存特征及渗流能力进行了研究。结果显示,长6段T2谱形态主要以左峰高右峰低型为主,可动流体饱和度差异较大,且整体偏低,渗透率与可动流体饱和度有良好的正相关关系。三种形态T2谱所对应不同品质的储层,渗流能力差异大;通过油水相渗实验发现,长6段整体束缚水和残余油饱和度较高,油相渗流能力差,随着储层品质变差,油水两相共渗区域也逐渐减小,两相共渗区域参数与可动流体饱和度也有较好的相关性。

Taking the Chang 6 low-permeability sandstone reservoir as an example, the authors used a series of experiments including nuclear magnetic resonance, casting thin slice,the SEM, oil-water relative permeability test. With all these techniques, we discussed the characteristics of movable fluids saturation and the seepage ability in Chang 6 reservoir inJiyuan oilfield. The research shows that, the saturation of movable fluids in Chang 6 reservoir is low, and has great differences, the T_2 spectrum is mainly bimodal pattern with high left side and low right side, and there is a quite good positive correlation between the saturation of movable fluids and the permeability. The three types of T_2 spectrum represent different reservoirs, the seepage ability also has differences. By using the oil-water relative permeability test, the result shows that Chang 6 reservoir has high bound water and residual oil saturation,the oil relative permeability is low, with the variation of the reservoir＇s quality, the seepage area with oil and water is becoming more narrow, the two characteristic parameters, the proportion of seepage area and the saturation of movable fluids also have a positive correlation.