Cheniers are ridges consisting of wave-reworked coarse-grained sediments, resting on top of muddy sediment (Augustinus, 1989;Otvos & Price, 1979). Cheniers may occur as a single ridge (e.g., in Demak, Indonesia) or they may be part of a chenier plain (e.g., in Louisiana, USA (Mcbride et al., 2007)), where multiple clusters of cheniers, separated by mudflats, are observed. Chenier coastlines consist of mostly very fine sediments, with a small fraction of coarser grained particles, which can have a marine or fluvial origin. For example, the chenier sediment in Tourville Bay, Australia is of local, marine origin (Belperio et al., 1988) while sand in the cheniers in French Guiana originates from sand supplied by local rivers rather than from the mud banks migrating alongshore (Anthony et al., 2010;Prost, 1989;Pujos et al., 2001). Cheniers can be formed in two ways, which are related to the origin of the coarser (sandy) sediments (Augustinus, 1989). Sand can originate from winnowing, where mud is brought into suspension and the remaining sand is transported onshore through wave-driven sediment transport, accumulating in a sandy ridge. Alternatively, cheniers may develop from spits forming downdrift of river mouths. In this paper, we will focus on the first mechanism: chenier formation through wave winnowing.Winnowing requires sufficient wave energy, for example, during a storm event (Woodroffe & Grime, 1999) or during a period of increased wave action (e.g., during inter-mudbank phases along the coast of the Guianas (Anthony et al., 2010;Brunier et al., 2019)). Furthermore, sufficient coarser-grained particles need to be available in the nearshore zone where waves create sufficiently high bed shear stresses to suspend the fines and mobilize the coarser sediments. For example, in the Louisiana Chenier Plain, cheniers are formed near the mouths of rivers discharging high fluvial sediment loads (Rosen & Xu, 2011). When higher waves coincide with spring tides,