Darrell Jackson & Michael Richardson 
High-Frequency Seafloor Acoustics 

The efficacy of sound to penetrate the seas made acoustic systems in the past century the leading tools for sensing objects in and measuring properties of the seas. For over sixty years The United States Office of Naval Research (ONR) has been a major sponsor of undersea research and development at universities, national laboratories, and industrial organizations. App- priately ONR is the sponsor of this monograph series. The intent of the series is to summarize recent accomplishments in, and to outline perspectives for, underwater acoustics in specific fields of research. The general field has escalated in importance and spread broadly with ri- ness and depth of understanding. It has also, quite naturally, become more specialized. The goal of this series is to present monographs that critically review both past and recent accomplishments in order to address the sho- comings in present understanding. In this way, these works will bridge the gaps in understanding among the specialists and favorably color the direction of new research and development. Each monograph is intended to be a stand-alone advanced contribution to the field. We trust that the reader will also find that each is a critical introduction to related specialized topics of interest as well.

Cuprins

Basic Concepts and Definitions.- The Nature of Marine Sediments.- Physical Properties.- Geoacoustic Properties.- Seafloor Roughness.- Sediment Heterogeneity.- Fluid Theories.- Elastic Theories.- Poroelastic Theories.- Reflection.- Seafloor Scattering Experiments.- Roughness Scattering Models.- Sediment Volume Scattering.- Acoustic Penetration of the Seafloor.- Backscatter Statistics.