A reverberation model based on the parabolic approximation is developed that includes sediment interface and volume perturbations. A multiple forward/single backscatter approximation is made, and the structure of the solution is found to depend on the two-way propagation with a scattering strength scaling dependent on the local properties of the perturbation. The model is implemented for continuous wave (CW) signals to predict mean reverberation pressure levels and for broadband pulse signals to generate complex reverberation structures in the time-domain. The spatial correlation and statistical properties of these predicted signals are then analyzed in an attempt to extract information on the underlying characteristics of the perturbation. Preliminary analysis suggests that reverberation due to the volume perturbations decorrelates more rapidly over depth than the reverberation due to interface fluctuations, although the differences appear small. Additionally, the statistical character of the reverberation structure due to the interface appears as a relatively flat spectrum, while the spectrum of the volume reverberation tends to appear colored. Attempts to correlate these characteristics with the structure of the perturbations is ongoing.
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