摘要
Prestackreversetimemigration（RTM）isanaccurateimagingmethodofsubsurfacemedia.TheviscoacousticprestackRTMisofpracticalsignificancebecauseitconsiderstheviscosityofthesubsurfacemedia.OneofthestepsofRTMissolvingthewaveequationandextrapolatingthewavefieldforwardandbackward;therefore,solvingaccuratelyandefficientlythewaveequationaffectstheimagingresultsandtheefficiencyofRTM.Inthisstudy,weusetheoptimaltime-spacedomaindispersionhigh-orderfinite-difference（FD）methodtosolvetheviscoacousticwaveequation.Dispersionanalysisandnumericalsimulationsshowthattheoptimaltime-spacedomainFDmethodismoreaccurateandsuppressesthenumericaldispersion.Weusehybridabsorbingboundaryconditionstohandletheboundaryreflection.Wealsousesource-normalizedcross-correlationimagingconditionsformigrationandapplyLaplacefilteringtoremovethelow-frequencynoise.NumericalmodelingsuggeststhattheviscoacousticwaveequationRTMhashigherimagingresolutionthantheacousticwaveequationRTMwhentheviscosityofthesubsurfaceisconsidered.Inaddition,forthewavefieldextrapolation,weusetheadaptivevariable-lengthFDoperatortocalculatethespatialderivativesandimprovethecomputationalefficiencywithoutcompromisingtheaccuracyofthenumericalsolution.
出版日期
2014年01月11日（中国期刊网平台首次上网日期，不代表论文的发表时间）
