Preconditioned Conjugate Gradient Algorithm-Based 2D Waveform Inversion for Shallow-Surface Site Characterization

Figure 7

Evaluation curves for the complex structure model noise-containing test. (a) Normalized misfits for the CG when the seismograms contain no noise and for the PCG when the seismograms contain no noise, 20% noise, and 50% noise versus the iteration number. (b) The RMSE for the CG when the seismograms contain no noise and for the PCG when the seismograms contain no noise, 20% noise, and 50% noise versus the iteration number. (c-d) The 1D S-wave velocity vertical profiles of the true model, initial model, and inversion results at distance = 10 m and distance = 35 m.

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