提高逆时偏移成像效果的若干关键处理技术

逆时偏移已广泛应用于复杂构造成像中，对于复杂构造的油气勘探起到了较大的促进作用。逆时偏移要求具有高质量的原始地震数据、高精度高分辨率的速度模型以及高精度的逆时偏移算法。为了处理近地表异常导致的数据异常、消除常规全波形反演存在“周期跳跃”现象、提高信噪比，研究了一系列具有针对性的前期处理技术和新的全波形反演技术等，并为逆时偏移设计了一套新的处理流程，包括空间地震子波一致性相位校正、近地表Q吸收补偿、基于模式的面波自适应衰减和基于模式的自适应全波形反演等。应用这些关键技术可以得到高质量的地震数据以及高精度、高分辨率的速度模型，最终改善成像效果，并已通过多口实钻井证实提高了逆时偏移的成像精度。

Research on seismic processing technologies for improving RTM imaging

Reverse-time migration (RTM) has been widely applied for imaging complex structures,and it is playing an important role in exploring complex structures. RTM needs high-quality raw seismic data,precise velocity models and RTM algorithm. In order to reduce to the effects of near surface anomaly,avoid the cyclic skip arising out of conventional full waveform inversion (FWI),and improve SNR,we developed several preprocessing and FWI technologies,and built a new RTM workflow including surface-consistent phase correction of spatial wavelets,near-surface Q compensation,pattern-based adaptive ground roll attenuation and pattern-based adaptive waveform inversion (PAWI). These technologies can provide high-quality seismic data,high-precision and high-resolution velocity models,and consequently improve the image of geological structures. Data from several wells have proved these technologies effective to improve RTM imaging.