RAS脉冲中子测井评价技术研究及应用

Research and Application of RAS Pulse Neutron Log Evaluation Technology

长庆油田储层物性差、层间矛盾突出、非均质性强,单井产液量低。单一的饱和度测量模型难以满足长庆油田低孔隙度、低渗透率、低丰度储层饱和度测井和精细解释评价的需求。脉冲中子饱和度测井仪(RAS)集非弹性散射、俘获、氧活化等多个测量模式于一体,一次下井可采集丰富的能谱及时间谱信息。以中子与地层反应原理为基础介绍RAS测井仪器原理及仪器技术指标,结合长庆油田现有饱和度测井仪器分析RAS测井仪器适用性,结合裸眼井解释结论及储层动态监测数据对测井资料进行综合解释,总结出RAS剩余油饱和度测井资料解释方法。结合测井评价成果分析判断储层含水率,有助于部署高采收率方案,提高了剩余油饱和度资料利用率。

Changqing oilfield has poor reservoir physical properties,prominent interlayer contradictions,strong heterogeneity and low single well fluid flow.Single saturation measurement model is difficult to match low porosity,low permeability,low abundance reservoir saturation logging and fine interpretation in Changqing oilfield.RAS,a pulse neutron saturation logging tool,integrates with inelastic scattering,capture,oxygen activation and other measurement modes,which can collect energy spectrum and time spectrum information in a single well.Based on the principle of neutron and formation reaction,this paper introduces the principle and technical index of RAS logging tool,analyzes the applicability combined with the existing saturation logging tools in Changqing oilfield,comprehensively interprets the logging data combined with the interpretation conclusion of open hole well and the dynamic monitoring data of reservoir and summarizes the RAS interpretation method of remaining oil saturation.In terms of analyzing and judging the water content of the reservoir and deploying the enhanced oil recovery scheme,the utilization rate of the remaining oil saturation data has been greatly improved.