时间谱测井气层识别方法在大庆油田的应用

Gas Reservoir Identification by Time Spectrum Well Logging in Daqing Oilfield

为了满足脉冲中子全谱测井仪(PNST)在大庆地区识别气层、合理解释地层孔隙度的需要,利用蒙特卡罗数值模拟方法建立了地层参数刻度井数值模拟模型,并以模拟井实测谱对模拟模型进行基准校验。基于数值模拟结果,按大庆油田常规套管井条件,研究孔隙中分别饱和油、水、气时,探测器计数率随孔隙度的变化规律,形成了基于时间谱分析的气层识别方法以及孔隙度解释模型。结果表明,利用改进的脉冲中子全谱测井时间谱解释方法,结合裸眼井测井资料进行综合分析,可快速、直观、精准地识别气层,并有效提高孔隙度解释精度。

In order to meet the need of identifying gas reservoirs by pulsed neutron spectrum logging tool(PNST)in Daqing oilfield and explain the formation porosity reasonably,a numerical simulation model of PNST in scale wells was established by Monte Carlo method.According to the conventional case hole conditions in Daqing oilfield,based on numerical simulation results,the change rule of the detector counting rate with the porosity was studied when the oil,water and gas were respectively saturated in the pores.The gas recognition method and the porosity interpretation model were formed.The results showed that the PNST logging curve could be used to identify the gas zone quickly and accurately with the comprehensive analysis of other open-hole well logging data,and the porosity interpretation model was effective in practical appropriate access to applications.