The role of biophysical cohesion on subaqueous bed form size: COHESION IN SUBAQUEOUS BED FORMS

Parsons, Daniel R.; Schindler, Robert J.; Hope, Julie A.; Malarkey, Jonathan; Baas, Jaco H.; Peakall, Jeffrey; Manning, Andrew J.; Ye, Leiping; Simmons, Steve; Paterson, David M.; Aspden, Rebecca J.; Bass, Sarah J.; Davies, Alan G.; Lichtman, Ian D.; Thorne, Peter D.

Abstract

Biologically active, fine-grained sediment forms abundant sedimentary deposits on Earth's surface, and mixed mud-sand dominates many coasts, deltas, and estuaries. Our predictions of sediment transport and bed roughness in these environments presently rely on empirically based bed form predictors that are based exclusively on biologically inactive cohesionless silt, sand, and gravel. This approach underpins many paleoenvironmental reconstructions of sedimentary successions, which rely on analysis of cross-stratification and bounding surfaces produced by migrating bed forms. Here we present controlled laboratory experiments that identify and quantify the influence of physical and biological cohesion on equilibrium bed form morphology. The results show the profound influence of biological cohesion on bed form size and identify how cohesive bonding mechanisms in different sediment mixtures govern the relationships. The findings highlight that existing bed form predictors require reformulation for combined biophysical cohesive effects in order to improve morphodynamic model predictions and to enhance the interpretations of these environments in the geological record.

Citation

Parsons, D. R., Schindler, R. J., Hope, J. A., Malarkey, J., Baas, J. H., Peakall, J., …Thorne, P. D. (2016). The role of biophysical cohesion on subaqueous bed form size: COHESION IN SUBAQUEOUS BED FORMS. Geophysical research letters, 43(4), 1566-1573. https://doi.org/10.1002/2016gl067667

• Journal Article Type: Article
• Acceptance Date: Jan 22, 2016
• Online Publication Date: Feb 19, 2016
• Publication Date: Feb 28, 2016
• Deposit Date: Dec 21, 2016
• Publicly Available Date: Dec 21, 2016
• Journal: Geophysical research letters
• Print ISSN: 0094-8276
• Electronic ISSN: 1944-8007
• Publisher: American Geophysical Union
• Peer Reviewed: Peer Reviewed
• Volume: 43
• Issue: 4
• Pages: 1566-1573
• DOI: https://doi.org/10.1002/2016gl067667
• Keywords: General Earth and Planetary Sciences; Geophysics
• Public URL: https://hull-repository.worktribe.com/output/446423
• Publisher URL: http://onlinelibrary.wiley.com/doi/10.1002/2016GL067667/abstract;jsessionid=16C1EFE61E8669295E4C3254F5D32D9F.f03t03
• Additional Information: Copy of article: Parsons, D. R., et al. (2016), The role of biophysical cohesion on subaqueous bed form size, Geophys. Res. Lett., 43, 1566–1573, doi:10.1002/2016GL067667.