起伏地表无网格井中地震Q补偿逆时偏移成像方法OA北大核心CSTPCD

Borehole seismic theoretically offers advantages such as high signal-to-noise ratio,wide frequency band,rich wave-field information,and strong reservoir identification capabilities,allowing for detailed reservoir imaging around the well.How-ever,the source energy of borehole seismic is weak,resulting in stronger absorption attenuation effect in subsurface media com-pared to surface seismic.Furthermore,irregular topography and complex structure around the borehole significantly impact fine migration imaging.Therefore,it is essential to develop an attenuation compensation migration imaging method suited for irregu-lar topography in borehole seismic.Using the principle of radius-basis-function finite-difference method,we establish a high-precision meshfree radius-basis-function finite-difference method with irregular topography of viscoacoustic wave equation.This method introduces a mixed Gaussian cubic basis-function and designs a node generation strategy for irregular topography.In ad-dition,we apply this method to the improved viscoacoustic wave equation based on Kelvin-Voigt model to implement an efficient and stable Q-compensated reverse time migration.The results demonstrate that the proposed Q-compensated reverse time migra-tion imaging method can achieve high-precision imaging of irregular topography for borehole seismic with attenuation compensa-tion,effectively restoring the profile energy,correcting phase distortion,balancing energy distribution in the profile,and im-proving imaging quality.