Description, Analysis, and Prediction of Sea-Floor Roughness Using Spectral Models

A method has been developed which allows a valid statistical model of the variability of oceanic depths to be derived from existing digital bathymetric soundings. The bathymetry of the world ocean has been mapped using a variety of acoustic sounding instruments and traditional contouring methods. The bathymetric contours represent a low-frequency, deterministic model of the seafloor. To describe the higher frequency variability, or roughness, of the seafloor requires the development of an appropriate statistical method for generating a valid stochastic model. The smooth contoured surface often preserved as a geographic grid of depths, when supplemented by such a roughness model, provides a complete description of the relief. The statistical model of the seafloor roughness is also a valuable tool for predicting acoustic scattering and bottom loss, and in addition contains a wealth of geological information for interpreting deep-sea processes.