地震叠前时间偏移处理技术

Seismic pre-stack time migration techniques

叠前时间偏移处理技术对速度场精度的要求较低,在构造复杂但速度横向变化不大的情况下有较好的成像效果,近年来在中国石油天然气股份有限公司各探区得到高度重视和推广应用。对叠前时间偏移处理的关键技术(叠前去噪、振幅补偿、反褶积、静校正、速度建模)进行了分析总结,并对其在富油凹陷整体评价、复杂断块精细勘探、碳酸盐岩岩溶地形识别、岩性地层油气藏勘探等方面的应用效果进行了分析,实践证明,叠前时间偏移是一项具有明显技术优势、应用前途广阔的地震精确成像技术,适合于在横向速度变化不大地区的地震资料处理。

Prestack time migration processing does not require highly of velocity fields. It can get a good imaging result in the circumstance of a complex structure and smooth lateral variation of velocity field. Thus it has gained much attention and wide applications in prospect areas in PetroChina. The key techniques involved in prestack time migration processing such as prestack noise attenuation, amplitude compensation, deconvolution, static correction and velocity model building are summarized, and their application effects are also analyzed in the overall assessment of oil-abundant sags, the elaborate exploration of complexly faulted blocks, the identification of carbonate karst topography and the exploration of stratigraphic reservoirs. The results prove that prestack time migration is an accurate seismic imaging technique with an evident technical preponderance and broad application prospects, being suitable for seismic data processing in the areas of smooth lateral variation of velocity field.