Characterizing seabed sediments using multi-spectral backscatter data in the North Sea

Characterizing seabed sediments using multi-spectral backscatter data in the North Sea

Bai, Q. (TU Delft Aircraft Noise and Climate Effects)
Mestdagh, S.M.F. (TU Delft Aircraft Noise and Climate Effects)
Snellen, M. (TU Delft Control & Operations)
Amiri Simkooei, A. (TU Delft Optical and Laser Remote Sensing)

Control & Operations

2023

Acoustic classification using single-beam and multi-beam echosounders has been widely applied in characterizing seabed sediments. Although previous studies have shown a better discrimination of fine and coarse sediments using multi-spectral echosounder data, analysis regarding comprehensive seabed sediment properties is still needed. In this study, we used single-beam data of 24 kHz, as well as multi-beam data of 90 and 300 kHz to investigate the benefits of multi-spectral backscatter data in describing sediment properties including median grain size; weight percentages of gravel, sand, and mud; volume percentages of stones, shell fragments, and living bivalves; as well as density of acoustically hard animals (molluscs and the tube-building worm Lanice conchilega). We classified data of each frequency in an unsupervised manner, using K-means clustering for the single-beam echo time series and Bayesian classification for the multi-beam backscatter. Compared with the top-layer sediment properties, we found classification of 90 and 300 kHz consistent with variations of median grain size and L. conchilega density, whereas classification of 24 kHz can also be related to the percentages of shell fragments and stones. In addition, one acoustic class of 24 kHz might indicate a higher gravel content in the subsurface of the study area. Although quantitative relationships between backscatter and sediment properties are still difficult to achieve given a limited number of samples, using multi-spectral backscatter data is a potential approach to characterize seabed sediments from various perspectives.

acoustic classification
backscatter
multi-beam echosounder
multi-spectral
North Sea
seabed sediment
single-beam echosounder

http://resolver.tudelft.nl/uuid:c569068a-375d-4ba7-a7a5-9940aa4c3d3a

https://doi.org/10.1109/OCEANSLimerick52467.2023.10244650

IEEE

2023-12-08

9798350332261

OCEANS 2023 - Limerick

OCEANS 2023 Limerick, 2023-06-05 → 2023-06-08, University of Limerick Concert Hall, Limerick, Ireland

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

conference paper

© 2023 Q. Bai, S.M.F. Mestdagh, M. Snellen, A. Amiri Simkooei