一种补偿介质吸收叠前时间偏移技术

A deabsorption prestack time migration technology

通过引入描述黏性吸收的等效Q值参数,发展了补偿介质吸收的叠前时间偏移方法。该方法基于地表观测数据建立等效Q值模型,应用补偿因子的光滑性阈值控制解决介质黏性吸收补偿的稳定性问题。基于倾角域菲涅尔带估计,结合稳相偏移的补偿介质吸收叠前时间偏移技术能够在压制介质吸收补偿噪声的同时提高计算效率。利用多流、双缓存机制实现补偿介质吸收叠前时间偏移的GPU/CPU协同计算,缩短了计算时间。大庆油田实际地震数据的应用结果表明,该技术可恢复地震波中被衰减的高频成分,提高地震成像的分辨率,其成果数据支持了大庆油田扶余油层致密油的水平井勘探部署。

A deabsorption prestack time migration scheme is developed by introducing an equivalent Q parameter to compensate for the absorption and dispersion.The equivalent Q can be established using surface seismic data during migration. Stabilization is achieved by applying a smooth, maximum limited gain function that matches the exact amplitude compensation factor when it is less than the user-specified gain limit.Based on an estimate of the Fresnel zone, the deabsorption prestack time migration was further improved by incorporating a dip-angle domain stationary phase implementation. It significantly attenuates the noises induced by the compensation and improves the efficiency of deabsorption prestack time migratiorzAn asynchronous double-buffering and multistream scheme was used to perform the GPU/CPU parallel computing.Data examples from the Daqing oilfield demonstrate that the proposed deabsorption prestack time migration software can help recover the attenuated high frequency components and enhance imaging resolution.The results support the deployment of horizontal wells deployment in tight oil reservoirs in the Fuyu oil layer of the Daqing oilfield.