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Acoustic wave propagation in low-attenuation bounded media produces long-lasting reverberation signals. Traditional non-destructive testing and imaging methods typically rely only on the first-arrivingwave packets, overlooking possible information contained in the later reverberating part (the codas).In this work, these codas are processed in order to compute the scattering cross section of a heterogeneity in a thin elastic plate using a statistical model for reverberation developed in earlier works. More precisely, within the frame of this model, a mathematical expression linking the scattering cross section to the mean of the squared envelope of the reverberated signals. Separately, Chehami etal. developed a beamforming-based imaging method (taking into account the dispersion) enabelingprecise localisation of the defect. Building on these contributions, the present work demonstratesthat defects can be characterized using only two parameters: their scattering cross-section and thecontrast in the corresponding localisation image. Numerical simulations, in which ultrasonic signalsin the 10–30 kHz range (A0 Lamb mode) were recorded at multiple known positions on the platesurface, were conducted on a small cylindrical defect. The scattering cross-section was first estimatedusing nonlinear fitting applied to the averaged envelopes of reverberated signals and compared withboth a theoretical model developed in Norris and Vemula’s works and a conventional approachbased only on direct wave arrivals. Image contrast was then computed from localization results. Finally, a characterization method is proposed adressing the inverse problem by combining thedefect’s scattering response with imaging contrast, expressed as a ratio relative to an isotropic defect.Promising preliminary results were obtained.