Acoustic Sensing Techniques for the Shallow Water Environment: Inversion Methods and Experiments

On the assessment of geoacoustic parameters in shallow water environments.- Bayesian inversion of seabed reflection data.- Backpropagation techniques in ocean acoustic inversion: time reversal, retrogation and adjoint model – A review.- Acoustic inversion at low kHz frequencies using an active, vertical line array.- Dispersion of broadband acoustic normal modes in the context of long range sediment tomography.- Characterization of local seabed properties using synthesized horizontal array data.- Characterization of a range-dependent environment from towed array data.- Accounting for bias in horizontal wavenumber estimates due to source motion.- Acoustic clutter from buried submarine mud volcanoes.- Nonlinear acoustical methods in the detection of gassy sediments.- Acoustic scattering from submerged and buried objects.- High-frequency bistatic scattering experiments using proud and buried targets.- A sediment probe for the rapid assessment of seabed characteristics.- Continuous acoustic monitoring of physiological and environmental processes in seagrass prairies with focus on photosynthesis.- Shallow water tomography in a highly variable scenario.- Inversions of reflection loss measurements of a smooth water/sand interface.- Estimation of transmission loss and its uncertainty.- A forward model for geoacoustic inversion based on ray tracing and plane-wave reflection coefficients.- Inversion of the propeller harmonics from a light aircraft for the geoacoustic properties of marine sediments.- Inversion of shallow water ambient noise data by means of differential evolution as a global search method.- Reflection loss and sub-bottom profiling with ambient noise.- Inversion of geoacoustic model parameters using ship radiated noise.- Matched-field processing of humpback whalesong off eastern Australia.- Inversions of horizontal and vertical line array data for the estimation of geoacoustic model parameters.- Issues of environmental variability in inverse problems in ocean.

This volume contains the collection of papers from the second workshop on Experimental Acoustic Inversion Techniques for Exploration of the Shallow Water Environment.
Acoustic techniques provide the most effective means for remote sensing of ocean and sea floor processes, and for probing the structure beneath the sea floor. No other energy propagates as efficiently in the ocean: radio waves and visible light are severely limited in range because the ocean is a highly conductive medium. However, sound from breaking waves and coastal shipping can be heard throughout the ocean, and marine mammals communicate acoustically over basin scale distances.
The papers in this book indicate a high level of research interest that has generated significant progress in development and application of experimental acoustic inversion techniques. The applications span a broad scope in geosciences, from geophysical, biological and even geochemical research. The list includes: estimation of geotechnical properties of sea bed materials; navigation and mapping of the sea floor; fisheries, aquaculture and sea bed habitat assessment; monitoring of marine mammals; sediment transport; and investigation of natural geohazards in marine sediments.
Audience
This book is primarily intended for physicists and engineers working in underwater acoustics and oceanic engineering. It will also be of interest to marine biologists, geophysicists and oceanographers as potential users of the methodologies and techniques described in the book contributions.

Comprehensive account of state-of-the-art research by leading scientists in the field Emphasis on experimental procedures and results Wide range of applications from marine biology to geophysics and sonar systems Includes supplementary material: sn.pub/extras