摘要
为了在叠前偏移中沿波场传播路径补偿黏滞性介质的吸收衰减效应,提高地震分辨率,首先导出黏滞声学介质条件下的波场频散关系,引入等效Q值实现频率域波场延拓,基于稳相原理求出波场延拓的渐近解,利用反褶积成像条件得到成像结果,并给出了偏移算法稳定性和数据高频折叠的处理方法,研制出工业化应用软件,完成多个三维工区的地震数据处理。另外,根据VSP资料,正演分析了松辽盆地的地层吸收对地震波场传播的衰减效应。与现有常规叠前时间偏移结果相比,黏滞声学介质吸收补偿地震叠前时间偏移在保护地震低频成分的前提下展宽频带15Hz左右,大幅提高了地震成像分辨率。
To improve seismic resolution,we propose in this paper a prestack time migration with compensating viscous media absorption along wave paths.Firstly,we deduce wave dispersion relation in viscous-elastic media condition.Then we carry out wave continuation by introducing an equivalent Q model.Finally we calculate an asymptotic solution based on stationary theory,and obtain image results with deconvolution imaging condition. A commercial software package has been developed with these algorithms,and is used in a few seismic projects.Furthermore,the absorption and attenuation are analyzed based on forward modeling on VSP data in Songliao Basin.Compared with conventional prestack time migration,the proposed prestack time migration can widen 15 Hz for seismic bandwidth with amplitude preservation,which improves greatly seismic imaging resolution.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2016年第2期325-333,207,共9页
Oil Geophysical Prospecting
关键词
黏弹性介质
衰减
频散
叠前时间偏移
等效Q值
波场延拓
地震分辨率
viscous-elastic media
attenuation
dispersion
prestack time migration
equivalent Q model
wave continuation
seismic resolution
