DT-tbx website | underwater sediment mapping

Knowledge o underwater sediment properties is important in different environmental contexts. It is needed for:

sonar communications,
biodiversity monitoring (see this twin),
detection of buried objects (see this twin).

Over the ten-year period 2001-2011, my group was involved in numerous projects, leading up to a three-week mission at sea, where real-time inversion was performed using sockets, as described in this post.

Mathematically, we have a classical imaging inverse problem to solve:

The imaging problem: given a source and an array where measurements are obtained, find the properties of the unknown medium.

This model is readily adapted to a realistic context of underwater sedimentology characterization, as shown below.

The sediment characterization problem, including geoacoustics : given a source and a receiver array, where measurements are obtained, find the properties of the unknown medium, both water and seafloor.

We have successfully performed inversion of the sediment properties and the sound-speed profile in the water layer, using an adjoint approach (Hermand et al., 2006).

Ocean acoustics tomography for recovering the soud-speed profile (left). Geoacoustic inversion for recovering the sediment properties (right.) Click on images to zoom.

References

JASA

Adjoint-based acoustic inversion for the physical characterization of a shallow water environment

Hermand, JP., Meyer, M., Asch, Mark, and Berrada, M.

J. Acoust. Soc. Am. 2006

Bib HTML

@article{Hermand2006a,
  title = {Adjoint-based acoustic inversion for the physical characterization of a shallow water environment},
  author = {Hermand, JP. and Meyer, M. and Asch, Mark and Berrada, M.},
  journal = {J. Acoust. Soc. Am.},
  year = {2006},
  month = jun,
  number = {6},
  pages = {3860--3871},
  volume = {119},
  keywords = {underwater sound, acoustic wave propagation, inverse problems, acoustic tomography, acoustic field, acoustic wave velocity, acoustic signal processing},
  owner = {Mark},
  publisher = {ASA},
  timestamp = {2010.01.14},
  url = {http://link.aip.org/link/?JAS/119/3860/1},
  abbr = {JASA},
  html = {https://asa.scitation.org/doi/full/10.1121/1.2197790},
  bibtex_show = {true}
}