Nonlinear geoacoustic inversion via parallel tempering

The method of parallel tempering is applied to achieve efficient and effective sampling of a particularly challenging multi-modal problem involving the inversion of acoustic reverberation data for geoacoustic and scattering parameters. Metropolis-Hastings sampling (MHS) and parallel tempering are compared for Bayesian geoacoustic inversion of simulated (noisy) reverberation data. A range-independent seabed model is assumed for the reverberation inversion problem in which the seabed is represented by an upper sediment layer of thickness 5m, sound velocity 1470 m/s, density 1.4 g/cm ³, and attenuation 0.5 dB/wavelength. The standard deviation of the data errors 1dB is also considered an unknown parameter in the inversion. Considering the parallel-tempering results, it is found that the multi-modality of the joint marginals are mapped out far better using parallel tempering samples using MHS. There is little practical difference in results for different there is little practical difference in results for different.