济阳坳陷埕北地区变质岩储层特征与测井解释

针对济阳坳陷埕北地区变质岩油藏有效储层识别和储层参数解释中的难点,在变质岩储层特征研究的基础上,利用补偿中子—自然伽马交会图与暗色矿物含量识别岩性的方法可有效区分煌斑岩类、花岗岩类和闪长岩类。通过FMI测井和裂缝指示曲线对储层裂缝进行识别。采用核磁共振分析孔隙度、FMI分析缝洞孔隙度与声波时差计算有效孔隙度、三孔隙度法计算缝洞孔隙度交互验证完成储层孔隙度解释,两者平均绝对误差为±1%左右。采用体积分配法和核磁共振测井饱和度解释,确定了储层含油饱和度。在储层四性关系研究基础上,制定了太古界有效储层识别标准,太古界主要含油岩性为片麻岩,含油性标准定为荧光以上(含荧光),有油气显示井段电阻率一般小于2000Ω·m,孔隙度一般大于3%,测试出油气井段全烃含量与无油气显示层全烃含量相对比值一般大于等于2。该方法在胜利油区太古界变质岩油藏储量计算中得到应用,实现了埕北地区和王庄地区变质岩油藏有效储层识别与储层参数计算,取得了较好效果。

Reservoir characteristics and logging interpretation of Chengbei metamorphic rocks in Jiyang depression

Based on the conclusion of the metamorphic rock reservoir characteristics in Archaean, which is difficult to identify the reservoir and parameters effectively. This paper presents the lithology identification by using the method of cross plot of CNL-GR logging data and content of dark mineral, based on research of reservoir characteristics of Chengbei metamorphic rock reservoir in Jiyang depression. The reservoir fracture identification through the FMI logging and fracture indicating curve is accomplished. This paper also applies porosity spectral analysis of FMI and porosity interpretation from normal logging to confirm the porosity of metamorphic rock fracture reservoir. Through the saturation calculation method of volume distribution and NMR logging, we can determine the reservoir oil saturation and formulate the effective reservoir identification standard. Based on this method, we have obtained a good result in identification of effective reservoir and parameters at Chengbeigu 7 and Shangu 6 blocks of metamorphic rock reservoir in Shengli oil field.