Open PhD position: Exploring the geomorphological controls on groundwater and streamflow resilience in crystalline basements 

Supervision: Clément Roques, associate professor, Luc Aquilina, Professor;

Collaboration: Laurent Longuevergne (Rennes), Kerry Leith (ETH Zürich) and Jean-Raynald de Dreuzy (Rennes).

Location: Observatoire des Sciences de l'Univers de Rennes, Université Rennes 1 Campus de Beaulieu Bât 15, 263 Avenue du Général Leclerc, 35042 RENNES (France)

The Groundwater Sustainability chair (www.clementroques.com) of the University of Rennes (France) aims at investigating the evolution of hydrological systems in response to climatic and anthropogenic forcings. We are looking to hire a PhD student who will explore the role landscape geomorphology in regulating groundwater and streamflow resilience in crystalline basements across the globe.

Context

Hydrological systems and associated ecosystems are highly sensitive to natural (climate, tectonics) and anthropogenic (resource exploitation, land use change, contamination) forcings, which raises questions about their long-term, potentially irreversible evolution. Crystalline basement regions are particularly sensitive to these forcings. This results from the strong heterogeneity of crystalline rocks, where groundwater is transferred through complex networks of fractures and faults, providing only limited groundwater storage capacities and poor hydraulic properties at the catchment scale. Recent studies have revealed a strong variability in recharge, storage and streamflow dynamics across catchments settled in crystalline basements. While the climatic controls on this variability have been the focus of abundant research, to what extent the geomorphological characteristics of the landscapes may control part of the variability remains an open question. 

This PhD project will aim at bridging this knowledge gap by exploring the interactions between geomorphology, landscape evolution and hydrology. The project will beneficiate from the emergence of new global datasets that combine ground-based observation, remote sensing measures and modelling interpolations, with remarkably fine resolutions. Recent advances in landscape evolution and hydrological modeling will also help to test the validity of the main hypothesis drawn from the data analysis.

Research plan

The student will specifically develop the following research tasks:

- Quantify the variability of hydrological systems and their resilience through the systematic analysis of time series of river flows, variations in groundwater levels, hydrogeochemistry and climatic parameters available at a global scale.

- Provide a mechanistic description of landscape geomorphologies to gain insights into the spatial distribution of fractures and discontinuities that may control groundwater flow and storage dynamics.

- Identify to what extent the variability in hydrological behaviors observed at the global scale can be explained by differences in geomorphological characteristics;

- Develop a modelling framework at relevant spatial and temporal scales that will be used to test the main hypothesis drawn from the global scale analysis.

In the late stage of the thesis, the student will also take part in other projects led by the Groundwater Sustainability chair. She/He will help to implement the results of her/his work in prediction models that will be used to test hypotheses regarding the evolution of hydrological systems under climate scenarios.  This work will be built around a multidisciplinary collaborative work involving researchers from national and international institutions (OZCAR, ETH Zürich, Oregon State University, among others), but also stakeholders in water management and specialists in the field of climate sciences.

Required skills

The successful candidate will have strong skills in applied hydrogeology and geomorphology, a passion for Earth sciences and willingness to work in multidisciplinary projects. Candidates with demonstrated skills in the analysis of big data are strongly encouraged to apply. Experience in Python base programming would be a must. The successful candidate must have an MSc in Earth Sciences, Environmental Engineering or related field and be strongly interested in research. This position will start in fall 2020 and last for three years.

How to apply

We look forward to receiving your online application by May 29, 2020. Please note that we exclusively accept online applications submitted at: https://theses.doctorat-bretagneloire.fr/egaal/theses-2020/controles-geomorphologiques-sur-les-ress/. Applications via postal services will not be considered.

For further information regarding the advertised position, please contact Dr. Clement Roques at clement.roques@univ-rennes1.fr or www.clementroques.com.

© 2017 by Clément Roques