عنوان مقاله [English]
Due to the drawbacks of beam-based seismic imaging methods, the use of wavefield-based imaging methods such as reverse-time migration (RTM) as a suitable alternative has been greatly welcomed in recent years. However, as the RTM is implemented using wave field reconstruction and cross-correlation imaging condition, it produces artifacts which is the major challenge of RTM. Therefore, in this paper, the inversion of seismic data is used by integration of RTM modeling operators and least squares migration to produce subsurface image. The least squares reverse time migration (LSRTM) method is implemented using the steepest decent and adaptive gradient methods in an iterative procedure including forward migration and inverse migration to solve the least squares problem. The LSRTM algorithm tries to fit a better depth model to the observed data based on the least-squares. Then the migrated images results of LSRTM procedure are presented using the steepest decent and adaptive gradient algorithms in different iterations which compared with each other and with conventional RTM. Finally, the misfit error and also the wavenumber spectra versus normalized amplitude has been compared for the disputed methods.