A simple Reverse-Time Migration (RTM) Acoustic Wavefield Extrapolator, A 2nd order Finite Difference Method program to solve/propagate (i.e., forward modelling) the 2D constant-density, wave equation on a Cartesian mesh, wth 2D for recievers' signals, 3D plots of wavefield and a movie; Acoustic-Cartesian-Waves ACW for RTM. Please cite this code as: Hussein Abduelhaleim Hussein Muhammed (2022), Least-Squares ReverseTime Migration in Pseudodepth Domain and Its Application. China University of Petroleum (East China), Master Thesis, School of Geosciences, Dept. of Geophysics. Library press©.