Sedimentology of a hypertidal point bar (Mont?Saint?Michel Bay, north?western France) revealed by combining lidar time?series and sedimentary core data

Intertidal meanders developed on salt marshes are known to expand and produce inclined heterolithic stratification rich in fine-grained sediments bear evidence for rhythmic deposition the upper part of inner meander bend (i.e. point bar). This occurs because lower point-bar deposits washed by strong currents, which remove mud drapes develop discontinuous record tidal cycles. Although these criteria widely accepted, facies models bars still lack a three-dimensional perspective overlook along-bend variability sediment distribution. The present study focuses hypertidal bar belonging upper-intertidal domain Mont-Saint-Michel Bay (France), it analyses sedimentology 3D time-framed accretionary package formed between 28 March 2012 29 November means lidar topographic data, geomorphological field surveys sedimentological core data. To define package, data from thirteen (light detection ranging) were used create synthetic stratigraphy. Data show that over period expanded alternating along its seaward landward sides, pointing out occurrence depositional patterns more complex than simple progressive expansion bend. thickest accumulated point-bar-apex zone, where largest amount was also stored. High accretion bend-apex zone is ascribed development low-energy conditions due flow bed configuration. rate promoted better preservation rhythmites, almost missing sides. remarks rhythmites within intertidal-point-bar controlled, not only their elevation with respect range, but location bar.