地震资料叠前深度偏移连片处理关键技术

Key technologies of seismic data pre-stack depth migration multi-survey joint processing

地震资料连片叠前深度偏移处理目前仍旧存在着区块间能量不均、频率差异、空面元、覆盖次数差异大、速度难以求准等突出问题.针对以上现状,本文采用振幅匹配及匹配滤波等技术,确保区块间振幅能量分布,解决频率差异,保证子波特征分布均匀,无闭合差存在;研究并采用了两步法数据规则化方法,即基于反假频傅里叶重构的空间内插和基于Voronoi多边形的振幅归一化技术,改善由于空面元和覆盖次数不均造成的偏移划弧现象.在此基础上,研究了叠前深度层析反演速度建模技术,解决连片速度问题,给出叠前深度偏移的速度体.将上述连片处理关键技术应用于实际资料后,偏移剖面无空间假频存在,成像效果明显提高,并在油田勘探中取得了显著的实际应用效果.

The Seismic Data multi-survey joint pre-stack depth migration （PSDM） processing is facing problems such as energy uneven, frequency difference, empty binning, coverage difference and inaccurate velocity. More than the status quo, amplitude matching and frequency matching filter are given is this paper to solve the frequency differences between blocks, to ensure wavelet features evenly distributed without misclosure there~ Data reconstruction of space-based anti-aliasing Fourier interpolation, only interpolate empty cells, on this basis, to carry out the Voronoi polygon-based amplitude normaliation to solve empty collection as well as the uneven coverage. On this basis, we use PSDM tomographic inversion velocity modeling techniques, to solve the problem of inaccurate velocity in multi- survey ioint blocks, and the final velocity body is proposed for PSDM. The results shows that the proposed key technologies can obviously improve the processing quality, and there is no spatial spurious frequency of the migration section, and has made actual application effection in oil exploration.