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Titre : | Évolution du couple Érosion/Sédimentation entre la Baie de Somme et la Baie de l'Authie |
Auteurs : | Domitille DE HAUTECLOCQUE ; Domitille DE HAUTECLOCQUE |
Type de document : | Mémoire d'initiation à la recherche |
Année de publication : | 2020 |
Concepts : |
DUNE
ACCRETION EROSION PLAGE TOURISME MORPHOLOGIE VENT TOPOGRAPHIE GRANULOMETRIE |
Résumé : | This work aims at visualizing and understanding the morphological evolution of the beach located between the Baie de Somme and the Baie de l'Authie. This zone, which is very touristy in summer and highly anthropized, has the particularity of being bordered by a line of mussel beds between the commune of Quend-Plage and the north shore of the Baie de Somme. This study is the extension of a regular monitoring financed by the Syndicat Mixte Baie de Somme - Grand Littoral Picard. The field campaigns are biannual, in September 2019 and in February 2020, to visualize and quantify the morphological evolution of the beach between the summer and winter seasons. During these two campaigns, a topographic data survey using a D-GPS and sand samples were taken in order to generate visualization maps of hydro-sedimentary cell displacement with ArcGIS software. The sand samples were processed in the laboratory to be usable by different software. With the multiple maps, we observed a morphological modification of the beach very different according to the zones; at the foot of the dune, an accretion which can go up to 3m on the southern zone bordered by the wooden piles, an erosion which can go up to 1.5m on the Quend-Plage zone and up to 3m in the northern zone. It has been shown that this non-constant variation is due to forcing agents such as wind, swell, tides, or anthropological activities. They are the ones that determine which areas are accreting and which are eroding. |
Spécialité : | Géologie |
Numéro de promo : | 82 |
numéro MIR : | 878 |