基于GPU的三维起伏地表单程波叠前深度偏移

3D one-way wave equation prestack depth migration from topography based on the acceleration of GPU

相对于双程波逆时偏移,单程波叠前深度偏移具有计算效率高、高频信息保持好且易于提取成像道集等优势,适用于我国陆上高陡构造不甚发育探区。为满足陆上复杂地表三维探区海量地震数据成像的需求,发展了基于GPU平台的三维起伏地表裂步傅里叶(Split-Step Fourier,SSF)叠前深度偏移技术,并引入了单程波偏移的相位校正技术以及基于分布式炮域成像结果的偏移距域道集并行提取技术。陆上复杂断块及缝洞探区实际资料成像试处理表明:基于GPU的三维起伏地表单程波叠前深度偏移成像方法不仅计算效率高,而且能较为准确地刻画复杂断块及缝洞储集体,在横向变速不太剧烈及陡倾构造不甚发育的探区具有很高的应用价值。

Compared with two-way wave equation reverse time migration,One-way wave equation migration possesses several attractive features such as higher computational efficiency,better bandwidth imaging result（particularly rich in high-frequency signals）and more flexible to obtain common imaging gathers（CIGs）.It is adaptable for many domestic land seismic exploration areas without high-dip structures.Aiming at huge 3-D land seismic data of complex surface exploration areas,we present 3Done-way wave equation prestack depth migration from topography based on the acceleration of GPU,using split-step Fourier（SSF）operator.In addition,we introduce a phase correction technique for one-way wave equation migration result and an offset domain CIGs extraction technique based on distributed shot images.Two typical land data examples of complex fault imaging and fracture-cavity reservoirs imaging illustrate that our method can describe these reservoirs relatively precisely with high computational efficiency,so it has a high value of practical application to the exploration areas without strong lateral velocity variation and high-dip structures.