discussion and conclusion

Migration algorithms extract the depth locations and relative amplitude behavior of reflectors in the earth from measured seismic data. However, these classic approaches cannot give a quantitative estimate of the reflectivity. In fact, seismic-wave imaging can be performed with the operator and matrix operations, based on least-squares inverse theory. The inverse imaging approaches have the potential to generate quantitive estimates of the reflectivity and to cope with seismic-data regularization and seismic-wave illumination. The ideas we proposed using these theories will open avenues for further research.