Amplitudes and shapes of seismic patterns derived from to-mographic images often are strongly biased with respect to realstructures in the earth. In particular, tomography usually pro-vides continuous velocity distributions, whereas major velocitychanges in the earth often occur on first-order interfaces. We pro-pose an approach that constructs a realistic structure of the earththat combines forward modeling and tomographic inversion(FM&TI). Using available a priori information, we first constructa synthetic model with realistic patterns. Then we compute syn-thetic times and invert them using the same tomographic codeand the same parameters as in the case of observed data process-ing. We compare the reconstruction result with the tomographic image of observed data inversion. If a discrepancy is observed,we correct the synthetic model and repeat the FM&TI process.After several trials, we obtain similar results of synthetic and ob-served data inversion. In this case, the derived synthetic modeladequately represents the real structure of the earth. In a workingscheme of this approach, we three authors used two different syn-thetic models with a realistic setup. One of us created models, butthe other two performed the reconstruction with no knowledge ofthe models. We discovered that the synthetic models derived byFM&TI were closer to the true model than the tomographic in-version result. Our reconstruction results from modeling marinedata acquired in the Musicians Seamount Province in the PacificOcean indicate the capacity and limitations of FM&TI.
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