高柳区块四维地震可行性分析

FEASIBILITY ANALYSIS OF 4D SEISMIC IN GAOLIU ZONE

冀东油田高柳构造带为了勘探的需要进行过二次三维的采集,具备了四维地震研究的良好经济可行性,但四维地震研究还必须进行技术可行性分析。这里通过波阻抗差异分析和正演模型分析,发现高柳区块油层被水淹后引起的波阻抗相对增加了30%,远远超过经验法则所要求的4%。在正演模型中,油层段变成水层引起的差异振幅为上、下围岩段无波阻抗差引起差异(相当于噪音)振幅的4倍～5倍,说明本地区地质条件,油藏条件,地震采集条件能够满足四维地震的关键要求,四维地震技术是可行的。

For further exploration,Gaoliu tectonic zone in Jidong oil field has got twice 3D seismic acquisition.Technical feasibility for 4D(time-lapse) seismic research should be studied although its good economic feasibility.The analysis of wave impedance difference and forward modeling reveals that the impedance of oil reservoir after flooded by water increase 30% in Gaoliu block,much higher than 4% calculated by empirical method.According to the forward modeling research,the amplitude difference between oil layer and water layer is 4 ~ 5 times higher than the wall rock which has no amplitude difference(equivalent to noise).Therefore,the 4D seismic technology is feasible in Gaoliu block for the geology condition,reservoir condition and seismic acquisition condition which can meet the key demand for 4D seismic research.