Acoustic estimation of ferromanganese crust exposure and sediment cover in a Northwest Pacific seamount using statistical analyses of shipboard multibeam acoustic data

Abstract

The estimation of the distribution of ferromanganese crusts (FMCs) is determined using the threshold of backscatter intensity of the multibeam echo sounder in ground-truth data; however, this is not accurate. This study developed a method to quantitatively estimate the distribution of FMCs and thickness of the surface sediment (TSS) by determining the relationship between topographic features, backscatter intensity using statistical analyses. Thus, the exposure of FMCs and TSS was quantitatively evaluated with accuracies of 17% and 2.5 m, respectively. This method can efficiently estimate distributions of FMC and TSS of entire seamounts for the benefit of future mineral explorations.