辽东湾盆地L油田东营组储层地震反演预测

Seismic Inversion Prediction of Dongying Formation Reservoir in Liaodong Bay Basin

辽东湾盆地南部东营组油气资源丰富,发现了受构造和岩性双重控制的复杂油气藏,但其储层厚度薄、岩性横向变化大、分布复杂且非均匀性强,给油气勘探带来巨大困难。利用高精度的地震反演方法是解决复杂油气藏、预测薄层储层的有效途径。文章应用地震相控非线性随机反演方法对东营组目的层段进行叠后地震反演薄砂岩储层预测。通过对测井曲线重构和去压实校正,使声波测井曲线满足高精度反演的要求。首先在地震相界面约束下建立低频速度模型,再基于非线性随机算法提高反演结果的分辨率,结合随机模拟理论使得地震反演结果忠实于地震数据体。该储层地震反演能够有效提高地震资料的分辨率,反演结果能够表征地震波形变化及突出地质沉积特征,反演结果与实际钻井资料进行对比发现吻合率高且能够有效识别薄砂岩储层,精细刻画辽东湾盆地东营组储层分布,为下一步油气勘探开发提供了可靠的依据。

Dongying Formation in the southern Liaodong Bay Basin contains a series of complex reservoirs controlled by both structure and lithology.At present,industrial oil and gas flow have been obtained after drilling.The reservoir is thin and the lithology changes greatly laterally with complex distribution and strong heterogeneity,causing great difficulties to oil and gas exploration.High-precision seismic inversion method is an effective way to solve the complexity of such oil and gas reservoirs.In this paper,the seismic phase controlled nonlinear random inversion method is used to predict the thin sandstone reservoir after stacking seismic inversion in the target interval of Dongying Formation.By reconstructing and decompressing the logging curve,the acoustic logging curve can meet the requirements of high-precision inversion.Firstly,a low-frequency velocity model is established with the constraint of seismic phase interface,and then the resolution of inversion results is improved based on the nonlinear random algorithm.Combined with the random simulation theory,the inversion results agree with to the seismic data volume.Good results have been obtained in practical application in this area,which can effectively improve the resolution of seismic data.The inversion results can characterize changes in seismic waveform and highlight the geological and sedimentary characteristics.The inversion results are in good agreement with the actual drilling data and can effectively identify thin sandstone reservoirs.Based on the inversion results,this paper characterizes the reservoir distribution of Dongying Formation in Liaodongwan depression,which provides a reliable basis for further exploration and development.