Philippe Blondel – författare

Offshore drilling and constructions require exact knowledge of the geophysical properties of the seabed and sub-seabed, as unexpected objects can slow down or halt projects. This book presents the state-of-the-art in acoustic exploration of the seabed and sub-seabed, from initial designs in the 1980s to commercial contracting and operation of the Acoustic Corer™ in the last decade. The Acoustic Corer™ is a high-definition commercial acoustic sub-bottom imaging system, producing an “acoustic core” within which sub-seabed sedimentary characteristics and discrete buried objects larger than 0.5 m can be identified and mapped. It makes use of the innovative JYG-cross design, inspired by seismic reflection and uses Synthetic Aperture Sonar (SAS) multi-angle scattering in and within the seabed to deliver unprecedented imagery. This book was written by the inventor of these concepts, a known specialist in seabed acoustics, with help from an experienced academic and author. It is intended first and foremost as a “how-to” guide for offshore industries looking at techniques to make the installation of different types of structures safe and efficient.

Buried waste on the seabed is a major source of pollution. But, very often, waste sites are not known until a serious problem occurs, or are not adequately mapped. Recent examples around Europe include WWI and WWII ammunition dump sites (e.g. Beufort Dyke in the UK), dumped nuclear submarines in the Arctic Seas, clandestine or hidden toxic-waste in the Baltic Sea and the North Sea. Even if properly documented, waste sites evolve with time (dumped material can move with currents and tides, especially on a scale of decades; toxic-material barrels can corrode and leak). This book shows the results of a concerted EU-funded effort to tackle this problem and find innovative ways to identify and map toxic waste sites on the seabed, whether they have been covered with sediments or not. These results are applicable to any region on the seabed in the entire world.

Seafloor surveying with acoustic remote sensing has become a powerful tool for researchers and professionals seeking knowledge about the structure and behavior of the seafloor. In particular, sidescan sonar is proving to be the preeminent technique, but its data is often difficult to interpret due to the physics of acoustic remote sensing, and to the varied geological processes at play. This handbook not only presents all the fundamentals but also explains how to interpret sidescan sonar imagery and bathymetry. It fully explores the most recent advances, both in the technology and in the knowledge of marine structures, and provides deep insights for interpretation and decision-making. Broadly expanded and updated from the previous 1997 “Handbook of Seafloor Sonar Imagery”, this handbook is indispensable to oceanographers, resource exploiters, telecommunications engineers, and marine researchers of all kinds.