Dynamics of Sorted Bedforms on a Shallow Infralittoral Prograding Wedge Influenced by Dredging (El Masnou, NW Mediterranean)

  • Ruth Durán
  • Belén Alonso
  • Gemma Ercilla
  • Ferran Estrada
  • David Casas
  • Araceli Muñoz
Chapter

Abstract

The dynamics of sorted bedforms on the inner shelf off El Masnou coast (NW Mediterranean) was investigated based on time-series of swath bathymetry and backscatter and grain-size analysis of grab samples spanning 4 years (2006–2009). The sorted bedforms are superimposed on the edge of a shallow infralittoral wedge with an orientation nearly perpendicular to the slope and oblique to the shoreline. They commonly display lateral asymmetry in backscatter, with the high backscatter domain on the depression and on the eastern side of the bedforms. The short-term evolution of these bedforms evidenced changes in the location of the bedform boundaries, widening and narrowing, predominant migration towards the southwest in the direction of the net alongshore sediment transport, and formation of new sorted bedforms. The analysis of repeated bathymetries also revealed the impact of dredging activities on the sorted bedforms, resulting in the destruction of part of the bedform pattern, which started to recover over the subsequent months. This behaviour suggests that the sorted bedforms off El Masnou are persistent and dynamic over a 4 year time span.

Keywords

Sorted bedforms Bedform dynamics Anthropogenic impact Inner shelf NW mediterranean 

Notes

Acknowledgments

This work was funded by the European BEACHMED-e project, an INTERREG IIIC Regional Framework Operation, and the FORMED project (CGL2012-33989) funded by the Spanish Ministry of Economy and Competitiveness. The authors wish to thank the Secretaría General de Pesca and Tragsa for the 2009 Espace Project dataset. R. Durán is supported by a CSIC JAE-Doc contract co-funded by the FSE.

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Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  • Ruth Durán
    • 1
  • Belén Alonso
    • 1
  • Gemma Ercilla
    • 1
  • Ferran Estrada
    • 1
  • David Casas
    • 1
    • 2
  • Araceli Muñoz
    • 3
  1. 1.Institut de Ciències del Mar (ICM-CSIC)BarcelonaSpain
  2. 2.Instituto Geológico y Minero de España (IGME)MadridSpain
  3. 3.Tragsa-SGPMadridSpain

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