Hydro Sedimentary and Morphodynamic Evolutions of - Mont-Saint-Aignan, France - M2C - Université de Rouen Normandie

Description

Hydro sedimentary and morphodynamic evolutions of the Somme Bay using a multi-scale and multi-sensor approach:

• Réf

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ABG-111176

• Sujet de Thèse 15/02/2023
• Autre financement public

• M2C

• Université de Rouen Normandie
• Lieu de travail
• Mont Saint Aignan
• Normandie
• France
• Intitulé du sujet
• Hydro sedimentary and morphodynamic evolutions of the Somme Bay using a multiscale and multisensor approach
• Champs scientifiques
• Terre, univers, espace
• Ecologie, environnement
• Mots clés dynamique sédimentaire, hydrodynamique, morphodynamique, télédétection
  Description du sujet:
• The estuaries and bays of the English Channel are very dynamic environments, under the combined action of strong tidal currents and swell climate, and are concerned with dense human activities. Hydraulic works realized during the previous centuries (channeling, embankment, land reclamation) have accentuated the unbalance of sedimentary fluxes between the bays and the coastal zone and it has thus favored strong sedimentation inside the bays. This sedimentation provides protection against coastal erosion. However, the rise in mean sea level could increase the risk of submersion and lead to stronger swell levels and, thus, cause a reversal of the sedimentation phenomenon, promoting erosion in front of the dykes and destabilization of the littoral barriers.
• The Somme Bay (North of France) is a sandy estuary mouth exposed to strong tidal (> 8m in spring tides) and swell conditions and with a low river flow (less than 30 m3/s). This bay fills with fine sands with a current rate up to 0.37 ±0.17 m in the lowest parts of the intertidal zone. However, at short time-scales (e.g. annual), the sediment budget can be variable, and some sectors of the bay can display erosion.
• The general objective of the thesis is to improve knowledge and comprehension of the main mechanisms controlling the sediment transfer, between the bay and the adjacent coastal zone and within the bay, and its morphodynamic evolution from monthly to multi-annual time steps.
• The methodology will be based mainly on in situ surveys to characterize the sedimentary and morphodynamic variability of the bay in response to hydrodynamic and meteo-marine forcings.-
• the local interaction between waves-currents, morphodynamics and sediment transport,

- transport modality between the coastal area, the intertidal area covering up to 80 % of the bay, the subtidal channels and the most upstream part enduring severe sediment settling,
- the variability of the sediment fluxes according to the different time-scales (tide, fortnight, seasonal, annual and pluriannual)
- the morphodynamic evolutions over several years (5-10 years) by reckoning the whole physical processes and their interactions.

• The Phd student will be located at M2C Rouen under the supervision of Julien Deloffre (M2C), Sophie Le Bot (M2C) and Nicolas Huybrechts (Cerema)

Prise de fonction:

• 02/10/2023
  Nature du financement:
• Autre financement public

Précisions sur le financement:

• CEREMA
  Présentation établissement et labo d'accueil:

• M2C

• Université de Rouen Normandie

Les recherches du laboratoire M2C s'intéressent à la caractérisation et à la modélisation de la dynamique des processus naturels et des différents compartiments, le long du continuum Terre-Mer, à différentes échelles de temps et d'espace. Les recherches s'organisent en 3 thèmes, 2 questions transverses et des pôles de compétences. Ces recherches sont réalisées avec une approche interdisciplinaire intégrant des chercheurs spécialisés en géosciences, océanographie, hydrologie, mécanique, microbiologie et biologie des organismes. Nos recherches couplent la mesure in situ, les approches expérimentales, la télédétection et la modélisation numérique.


Site web:


Intitulé du doctorat:

• Doctorat de géosciences
  Pays d'obtention du doctorat:
• France

Etablissement délivrant le doctorat:

• Université de Rouen Normandie

Ecole doctorale:

• Normande de biologie intégrative, santé, environnement
• Engineer or master degree in geosciences and/or coastal oceanography.
• Knowledge of coastal or marine environments, in sedimentology (cohesive/non cohesive), sediment dynamics and fluid mechanics. Experience in satellite imagery analysis, in situ measurements and/or data analysis will be appreciated. Autonomy, critic and curious mind.-
• 01/04/2023