核磁共振测井在低渗透油藏储量评价中的应用

The Application of NMR Logging in Low Permeability Reserves Evaluation

低渗透砂岩油藏由于孔隙结构复杂,利用常规测井进行油层识别和储层参数的定量解释有很大难度,影响了储量的升级和评价。以基山低渗透砂岩油藏为例,以核磁共振的原理为基础,从孔隙结构研究入手,利用T2分布谱分布形态特征和差谱、移谱分析进行了油层的识别,利用核磁共振T2谱对孔隙结构的研究确定了有效储层的物性下限,利用核磁共振可动流体孔隙体积进行了含油饱和度的计算。将核磁共振测井成果与常规测井资料相结合,明显提高了有效层识别和参数的解释精度,解决了低渗透油藏储量评价的难点,也为储量的评价和顺利上报奠定了基础。

Because the pore structure of low permeability sandstone reservoir is complex, it is very difficult to recognize and evaluate the net pay using conventional logging. As a result, the evaluation of reserves have been greatly affected. Based on the NMR principle in Jishan low permeability sandstone reservoir, net pay have been identified using T2 spectrum distribution and differential and shifted apectrum analysis, the physical properties cutoff of net pay thickness have been made through the pore structure research by NMR log, oil saturation has been interpreted using T2 spectrum as well. Combined the NMR logging with the conventional logging, the precision of recognition and parameter explanation of net pay are enhanced evidently. So the difficuties of low permeability sandstone reserves evaluation have been solved.