强反射背景下迭代低频模型在反演中的应用

Application of iterative low-frequency model in inversion under strong reflection background

储层预测的精度影响油气勘探开发的经济性,而针对复杂地质背景下的低频建模方法是提高储层反演预测精度的有效方法之一。为去除研究区特殊地质界面对储层反演造成的影响,提出了一种用以压制灰岩缝洞储层强反射引起的地震数据旁瓣效应的低频模型构建方法,以正演波动方程算法得到的地震数据为基础,迭代低频模型参与反演,逐步压制旁瓣效应的影响,最终使反演结果与地质模型一致。提出的低频模型迭代方法适用于碳酸盐岩缝洞型储层精细刻画,为储层定量解释提供合理的弹性参数,在奥陶系缝洞型储层预测中具有较强实用意义。

The accuracy of reservoir prediction affects the economy of oil and gas exploration and development,and the low-frequency model method is one of the effective methods to improve the prediction accuracy of reservoir inversion under complex geological background.In order to remove the influence of special geological interfaces in the study area on reservoir inversion,the authors in this paper put forward a low-frequency model construction method to suppress the side-lobe interference of seismic data caused by strong reflection in limestone fracture-cave reservoir.Based on the seismic data obtained from the forward wave equation algorithm,and the low-f requency model is iterated for inversion and the side-lobe interference is gradually suppressed,which finally makes the inversion to be consistent with the geological model.The low-frequency model iteration method proposed in this paper is suitable for the fine characterization of fracture-vuggy carbonate reservoir,and provides reasonable elastic parameters for quantitative interpretation of reservoir,which has strong practical significance in the prediction of Ordovician fracture-vuggy reservoir.