The study of the sedimentary nature of the seafloor is a key aspect to infer the spatial distribution of demersal fisheries resources (e.g., hake (Merluccius gayi peruanus)), to locate adequate zones for aquaculture farms, to examine biogeochemical processes occurred in the water column and to estimate the abundance of benthic organisms lying at the seafloor (e.g., Thioploca). The aim of this study is to infer, using acoustic backscattering mutifrequency information from an EK60 scientific echosounder (200 kHz, 120 kHz, 70 kHz, 38 kHz, 18 kHz), the bulk composition of the first meter of marine sediments located to the southeast of Hormigas de Afuera Islands, offshore Callao. This hydroacoustic multifrequency system is routinely used for the assessment of fisheries resources for the Peruvian Sea Institute (IMARPE). In this study we used backscattering information (Sv mean) from the first ...