【摘要】 叠前时间偏移生成的共成像点道集是海相碳酸盐岩天然气储层叠前预测的基础数据,要求具有较高的信噪比、分辨率和振幅保真性。叠前时间偏移共成像点道集中振幅相对关系受到破坏的一个重要原因,是野外地震数据偏移距空间分布的非均匀性。研究开发了具有针对性的叠前偏移距规则化技术——基于偏移距分布密度的叠前振幅加权方法,其实质是根据每个偏移距的空间分布密度确定适当的振幅比例因子,对所有分组后的共偏移距数据做振幅加权处理,再进行叠前时间偏移。选取了某个正在进行海相碳酸盐岩储层研究的勘探区域,采用上述方法消除了野外偏移距不规则分布造成的成像假象,得到了相对振幅特征保持良好、信噪比和分辨率明显提高的共成像点道集。更多还原

【Abstract】 Prestack prediction of marine carbonate gas reservoir is usually performed on common imaging point gathers produced by prestack time migration. Successful prediction relies on higher signal-to-noise ratio and resolution, as well as better amplitude preservation for common imaging point gathers. One of the main factors damaging amplitudes is the inhomogeneous offset distribution of filed data. In this paper, prestack offset regularization technique is applied to eliminate imaging artifacts in prestack time migration and provide amplitude-preserved common imaging point gathers with higher signal-to-noise ratio and resolution in an area of marine carbonate gas reservoir.更多还原