A conjugate gradient full waveform inversion program is coded to verify the effectiveness of full seismic waveform inversion and to study its characteristics. Firstly, a one dimensional inhomogeneous model is inverted using one source and one receiver. Then, by modifying different parameters of the inversion, the factors that affect the inversion result are discussed. It is shown that full waveform inversion can produce accurate result when data is abundant. The number of sources and stations is the primary factor that affect the inversion result. Multiscale inversion and better initial model can significantly improve the stability of the inversion. Noise applied to the observed seismogram can cause small scale disturbance on the result, though large scale characteristics of the result remain more or less unaffected.

A 2-D staggered grid pseudospectral and finite difference hybrid method is applied to perform numerical simulations of lunar seismic wave propagation in a laterally heterogeneous crustal Moon model. The relief of lunar crust and mantle interface is defined with different height, width and position based on the present lunar structural models. The effects of these factors on lunar records are discussed, respectively. How the lateral variations of Moon crustal thickness affects the strong wave coda of lunar signals is revealed. The results show that the height of the relief dominates the formation of strong wave coda, greatly affects the duration time and amplitude of the coda. The width of the relief has impact on the amplitude. The effect of position of the relief is complex, not only affecting the travel time of P and S waves, but also the duration time and amplitude of the coda.