EGU24-15693, updated on 09 Mar 2024
https://doi.org/10.5194/egusphere-egu24-15693
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Classification of underwater flow-transverse sedimentary bedforms

Alice Lefebvre1, Robert W Dalrymple2, Julia Cisneros3, Leon Scheiber4, Suzanne Hulscher5, Arnoud Slootman6, Maarten G. Kleinhans7, and Elda Miramontes8
Alice Lefebvre et al.
  • 1MARUM, University of Bremen, Germany (alefebvre@marum.de)
  • 2Department of Geological Sciences and Geological Engineering, Queen's University, Canada
  • 3Department of Geosciences, Virginia Tech, USA
  • 4Franzius Institute of Hydraulics, Waterways and Coastal Engineering Master of Science, Leibniz Universität Hannover, Germany
  • 5Department of Civil Engineering, University of Twente, The Netherlands
  • 6Department of Geology and Geological Engineering, Colorado School of Mines, USA
  • 7Department of Physical Geography, Utrecht University, The Netherlands
  • 8MARUM and Department of Geosciences, University of Bremen, Germany

Despite the recommendations given in Ashley (1990), a plethora of terms continues to be used to describe flow-scale flow-transverse sedimentary bedforms, often without clear definition or distinction between the different nomenclatures. For example, (marine) dunes and sand waves are used interchangeably in many contexts. Smaller bedforms superimposed on larger ones may be referred to as megaripples or secondary dunes. It is currently unclear if different terms are used due to intrinsic morphological or genetic differences or due to the traditions of different scientific communities. Ashley (1990) already noted that the “poor communication among scientists and engineers has perpetuated the multiplicity of terms”. Researchers from fluvial, coastal or deep-marine environments, from industry or academia, from various disciplines, such as sedimentology, oceanography, coastal and offshore engineering or geomorphology may use a specific vocabulary. Furthermore, terminology may differ depending on the country or research group in which they work. All this makes communication difficult and may cause misinterpretations, hindering progress in understanding and cross-disciplinary collaborative pursuits.

The aim of the present contribution is to provide an updated classification of the different types of underwater flow-transverse sedimentary bedforms. The intent is to homogenise the nomenclature for researchers coming from different disciplines and working in varied environments, to enable the use of a common classification and terminology to improve knowledge exchange, comparison and dialogue.

We propose a description table, which can be used by scientists and practitioners to describe the sedimentary bedforms with which they are working. Importantly, each bedform characteristic is described and the way to calculate the quantitative descriptive parameters is detailed. The description table aims at providing a standard and consistent way to describe the bedforms and their environmental setting prior to classifying them. The description table can be used independently of bedform type and further classification, which should overcome communication issues.

Two classification schemes are then proposed. The first is based on an understanding of the genetic processes. This should be used whenever possible because it informs about the underlying processes which formed the bedform. In order to complement the process-based classification, or in situations where the genetic processes are unknown, a second, geomorphological classification is introduced. Thus, we urge the bedform community to consider deploying these descriptor and classification tools and hope our contribution leads to a much more transparent and cohesive future in bedform research.

How to cite: Lefebvre, A., Dalrymple, R. W., Cisneros, J., Scheiber, L., Hulscher, S., Slootman, A., Kleinhans, M. G., and Miramontes, E.: Classification of underwater flow-transverse sedimentary bedforms, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15693, https://doi.org/10.5194/egusphere-egu24-15693, 2024.

Supplementary materials

Supplementary material file

Comments on the supplementary material

AC: Author Comment | CC: Community Comment | Report abuse

supplementary materials version 1 – uploaded on 15 Apr 2024, no comments