Improved drag coefficient and settling velocity for carbonate sands

Abstract

and bed load) using the Rouse number for 5 years of wave-induced bed shear stress on the North Shore beaches of Oahu, Hawai'i.

Sediment supply dampens the erosive effects of sea-level rise on reef islands

“…We note that reef-derived carbonate sediments have a wide range of characteristics (i.e. size, shape and density) which control entrainment and transport 47 and would differ based on the local sources of sediment. For this model, the most important scale relationships were identified, and the critical parameters were kept in similitude between model and prototype 48,49 .…”

On the settling of marine carbonate grains: Review and challenges

“…The effect of particle shape and density on settling velocity has been the topic of numerous investigations (Pettyjohn and Christiansen, 1948;McNown and Malaika, 1950;Fontein, 1960;Alger and Simons, 1968;Stringham et al, 1969;Clift et al, 1978;Komar and Reimers, 1978;Gögüs ¸ et al, 2001;Le Roux, 1997, 2004, 2014Riazi and Türker, 2019), some of which are dedicated to carbonate sediment (Maiklem, 1968;Braithwaite, 1973;Kench and McLean, 1996;Paphitis et al, 2002;Smith and Cheung, 2003;Hodson and Alexander, 2010;Wang et al, 2018;Li et al, 2020;Riazi et al, 2020). Grain size provides a reasonable estimate of the hydrodynamic behaviour of most terrigenous sediments, enabling the interpretation of environmental processes and depositional energy-level of siliciclastic sedimentary deposits (Reed et al, 1975;Lund-Hansen and Oehmig, 1992;Kench and McLean, 1997).…”

“…Most recently, Riazi et al (2020) were the first to apply the strategy of Gögüs ¸ et al (2001) in splitting the drag coefficient into two components: a frictional drag coefficient C D,f that is dominant at low Re p in the laminar regime, and a pressure drag coefficient C D,p prevailing at high Re p in the turbulent regime. They used the dataset of Smith and Cheung (2003) and a small number of their own grains to derive the constants in Eq.…”

“…Despite the limited number of datasets and variability of grain properties, there have been recent attempts to derive empirical universal settling equations for bulk carbonate sands (Smith and Cheung, 2003;Alcerreca et al, 2013;Cuttler et al, 2017;Wang et al, 2018;Li et al, 2020;Riazi et al, 2020). Bulk carbonate sands are more heterogeneous and hence hydrodynamically more complex in comparison with siliciclastics.…”

“…For example, non-spherical shapes complicate the choice of which grain size should be used for highly irregular particles. Preceded by the pioneering studies of Berthois and Le Calvez (1960), Berthois (1965), Maiklem (1968) and Braithwaite (1973), several authors have reviewed particular aspects relevant to the settling of carbonate grains, including sediment properties (Ford and Kench, 2012), application of shape parameters (Barrett, 1980;Blott and Pye, 2008), analytical techniques McLean, 1996, 1997;Yin et al, 1999;Cuttler et al, 2017), hydrodynamic settling regimes (Allen, 1984;Smith and Cheung, 2003;Flemming, 2017), entrainment and transportability (Prager et al, 1996;Paphitis et al, 2002;Yordanova and Hohenegger, 2007;Kench, 2011;Riazi et al, 2020), and the variation in settling velocity of numerous carbonate-producing organisms (Hodson and Alexander, 2010).…”