chênier

OBS: Les ""chêniers"" (mot d'origine française: lieu planté de chênes) sont d'anciens cordons de plage avec sables quartzeux et coquilles. Ces cordons ont tendance à se ramifier (...)

OBS: The growth and extension of sand-shell ridges at salt marsh edges are effects which appear to be common at intervals in the history of many tidal flats. On the open coastline of southwestern Louisiana these ridges, or ""cheniers"", are known to extend in uninterrupted fashion for 48 km with average widths of 180 m and thicknesses of 2 m (...) The features common to all cheniers, whether large or small, is that they consist of a mixture of sand and shells transported from adjacent intertidal and subtidal areas. On the seaward face during active growth they rest on upper tidal flat sediments, whereas on the landward face they interdigitate with and rest unevenly on salt marsh sediments. The structures are usually asymmetrical with the steeper side facing landward; this is the direction in which they tend to move.