1. A system for classifying seafloor roughness using artificial neural network (ANN) hybrid layout from unprocessed multi-beam backscatter data, said system comprising a means for generating unprocessed multi-beam backscatter r.m.s. data attached to the input of a self-organizing map (SOM) preprocessor ( 20 ), said SOM preprocessor being attached through one or more Learning Vector Quantization (LVQ) variants ( 21 and 23 ) to a memory/display module ( 22 ).