Offer Description
Scientific background
Estuaries are dynamic geomorphological systems whose evolution results from complex interactions between sea-level variations, fluvial processes, hydroclimatic conditions, extreme events, sediment inputs from catchments, and anthropogenic transformations of coastal environments. Throughout the Holocene, these interactions have shaped complex morphosedimentary trajectories, characterised by phases of infilling, shifts in depositional environments, and the reorganisation of wetlands. More recently, the intensification of hydraulic engineering, wetland drainage, changes in agricultural practices, and coastal transformations have profoundly altered their functioning.
The Estuarix project, led by UMR M2C at the University of Caen Normandy, in collaboration with UR LUSAC (University of Caen Normandy-Intechmer Cherbourg), UMR IDEES (University of Rouen Normandy), UMR EPOC (Bordeaux), UMR LPG (Angers), and the Technical University of Denmark in Riso and University of Copenhagen (Denmark), aims to characterise the morphosedimentary responses of estuaries from Normandy to environmental changes associated with the transition towards the Anthropocene. The project is based on the study of sedimentary archives from several estuaries in order to place recent transformations within a long-term historical perspective and distinguish the effects of climatic and hydroclimatic forcing from those of human interventions.
The present position is part of the palaeoenvironmental and geoarchaeological component of the Estuarix project and will focus primarily on reconstructing the geomorphological and sedimentary evolution of two estuaries: the Saâne and the Risle. These estuaries provide particularly valuable case studies because of their geomorphological and anthropogenic histories, the evolution of their wetlands, and their past human occupation (e.g. Roman and medieval settlements). In the case of the Saâne, its recent reconnection to the English Channel, in December 2025, also provides a particularly relevant context for studying estuarine dynamics.
The study of Holocene sedimentary sequences will make it possible to characterise the infilling processes of these valleys, identify the main stages of their evolution, and gain a better understanding of the dynamics that have shaped their present-day configuration. The project will adopt an integrated approach combining geomorphology, stratigraphy, sedimentology, geochemistry, geochronology, and archaeological and historical data.
Scientific objectives
The main objective is to reconstruct the Holocene morphosedimentary trajectories of the Saâne and Risle estuaries and identify how these systems have responded to environmental and anthropogenic changes, with particular emphasis on the last few centuries, a period characterised by an intensification of human interventions and engineering works.
The research will aim to:
• Characterise the stratigraphic organisation and sedimentary infilling processes of the estuarine valleys;
• Establish a robust chronological framework to date the main phases of transformation of the study systems;
• Identify facies changes and transitions between fluvial, estuarine, marsh and peat-forming environments;
• Analyse grain-size and geochemical variations in sedimentary deposits in order to characterise sedimentation dynamics and changes in depositional conditions;
• Relate the changes recorded in sedimentary archives to climatic changes, potential extreme events, and anthropogenic transformations of catchments and coastal environments;
• Compare the evolutionary trajectories of several estuaries from Normandy in order to distinguish common processes from local specificities.
Main duties and responsibilities
1. Acquisition and characterisation of sedimentary archives
The postdoctoral researcher will contribute to the development of coring and sampling strategies, the preparation of applications for administrative permits, fieldwork campaigns, and the description of sedimentary sequences. They will characterise the geomorphological settings of the study sites, assess the continuity and quality of the available sedimentary archives, and help define analytical requirements in consultation with the supervisory team and in accordance with the scientific objectives.
2. Sedimentological, geochemical and geochronological analyses
The work will involve sample preparation and the analysis of sedimentary facies, grain-size variations and geochemical parameters, as well as the implementation of a geochronological approach combining radiocarbon dating and portable OSL measurements. Particular attention will be paid to the development of age-depth models, the assessment of chronological uncertainties, and the identification of potential discontinuities, reworking phases and interpretative limitations. The objective will be to achieve a temporal resolution suitable for identifying the main phases of environmental change and, where the sedimentary archives allow, short-lived events.
3. Reconstruction of palaeoenvironmental and geomorphological trajectories
The postdoctoral researcher will integrate stratigraphic, sedimentological, geochemical and chronological data to reconstruct the main stages of infilling and evolution of the two estuaries under investigation. The results will be compared with available geomorphological, historical, climatic, hydrological and archaeological data in order to assess the respective roles of natural forcing and anthropogenic transformations in the observed dynamics.
4. Inter-estuary comparison and scientific dissemination
A comparative approach will be developed across several estuaries from Normandy to identify common evolutionary trajectories, differences in system functioning, and the factors controlling their evolution.
The postdoctoral researcher will contribute to Estuarix project meetings, the preparation of research articles for international peer-reviewed journals, the presentation of results at scientific conferences, and the delivery of project outputs. They may also be involved in the occasional scientific supervision of students participating in fieldwork and laboratory activities.
Where to apply
E-mail: bernadette.tessier@unicaen.fr
Skills/Qualifications
Applicants must hold a PhD in Geosciences, Geomorphology, Sedimentology, Geology, Palaeoenvironmental Sciences or a related discipline.
The following skills and experience are expected:
• Experience in the analysis of sedimentary archives and stratigraphic interpretation;
• Expertise in geochronology, particularly OSL dating, and the development of age-depth models;
• Ability to integrate and interpret sedimentological, geochemical and geomorphological datasets;
• Proficiency in statistical processing and quantitative data analysis;
• Proficiency in Geographical Information Systems (GIS);
• Ability to undertake fieldwork, conduct scientific research activities, and write research articles in English.
Experience in estuarine and coastal environments or in the sedimentary records of peat-forming environments will be considered an asset. Knowledge of the Holocene geomorphological and climatic evolution of Normandy will also be an advantage.
Independence, scientific rigour, and the ability to work within a multidisciplinary research team will be particularly valued.
Additional Information
Benefits
Access to the analytical facilities and technical platforms of the various project partners.
Eligibility criteria
– degree of alignment with the required skills
– experience
– publications in the scientific field of the project
Selection process
Applicants should submit a detailed CV, a cover letter, their PhD examination report, a list of publications and conference presentations, and the contact details of two academic referees:
– the whole sent as a single pdf file by email to bernadette.tessier@unicaen.fr and dominique.todisco@univ-rouen.fr
– Final selection, following online interviews, from a shortlist of pre-selected candidates
Additional comments
Duration of the contract
12 months
Work location
The postdoctoral researcher will be hosted at UMR M2C, University of Caen Normandy (B. Tessier, L. Dezileau, T. Lortie).
He (she) will work in close collaboration with Dominique Todisco and Stoil Chapkanski at UMR IDEES, University of Rouen Normandy, in Mont-Saint-Aignan through regular research visits.
