1. Oversea Business Department, Geophysical Research Institute, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China; 2. Research and Development Center, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China
Abstract：With the development of geophysical exploration technology，least square migration （LSM） is catching increasing attention.Compared to conventional migration techniques，LSM can broaden the frequency band and improve seismic resolution，with advantages in illumination compensation and balancing of imaging amplitude.Thus，its migration results are closer to the reflection coefficient of the subsurface medium.In LSM，selecting appropriate migration parameters is crucial for the imaging quality of the migration results.Due to the time-consuming nature of the LSM algorithm，studying the effect of migration parameters on migration time is also of significance in practical production.Firstly，experiments with model data and actual data demonstrate that when the frequency band of the wavelet matches that of the data，LSM has the widest imaging frequency band and highest resolution.Additionally，the profile obtained by employing wavelets extracted from the data has a wider bandwidth and higher resolution than that by adopting Ricker wavelets.Then，a comparison is conducted between the LSM results of actual land data and offshore data to discuss the reasons for the less ideal result of the land data are the rapid spatial variation of wavelets.Finally，the experimental processing of actual data helps obtain an empirical relationship of the LSM computational time with processing frequency band and data volume，which can provide references for estimating the required time for actual project operation.
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