Postdoctoral research position in geodynamics: Thermal evolution of the lithosphere of the Aquitaine Basin (M/F)

Job Description

Missions

The objective of this post-doctoral research is to quantify the evolution of the thermal structure of the Aquitaine Basin's crust and mantle using the geological record.
Geophysical data, the subsidence history of sedimentary basins, and thermal-mechanical models indicate that the thermal structure of the European lithosphere remained stable during the Mesozoic, potentially due to small-scale convection at its base. To evaluate this hypothesis, the study proposes to cross-correlate thermal proxies, including changes in thermal buoyancies recorded in the elevation history, with existing and newly acquired temperatures inferred from mafic magma reservoirs hypothesized to exist at the base of the lithosphere beneath the French Massif Central and the Pyrenees.
Thermometric analyses of mineral assemblages (e.g., olivine-bearing basalts) will be used to estimate magmatic temperatures at the base of the lithosphere. Crustal cooling histories and potential thermal rejuvenation events will be reconstructed using existing low-temperature thermochronology and P–T–t data, contributing to a new lithotectonic map of the Aquitaine basement. The present-day lithosphere temperature structure will be modeled using petro-physical modeling (LitMod2D 2.0 software) along a ~1000 km transect (Paris Basin to Aquitaine Basin), incorporating constraints from topography, heat flow, gravity, geoid, seismic velocities, and recent mafic volcanic rocks (<10 Ma) as proxies for the mantle's thermal regime.

Activity

The postdoctoral researcher will conduct a tectonic synthesis of the Aquitaine Basin and its surrounding regions, with a focus on metamorphic and magmatic units. The role will involve participating in field sampling campaigns and performing whole-rock and microprobe analyses on newly collected basalt samples. Additionally, the researcher will update the Georoc database with bibliographic data published since 2015 and progressively develop a present-day lithospheric model using LitMod2D 2.0.

Your Profil

Skills

The candidate must have a strong background in geodynamics, with solid experience in the petrology of magmatic and/or metamorphic rocks, as well as an experience in the construction of crustal-scale tectonic cross-section and multi-scale studies of the continental lithosphere.

Your Work Environment

The postdoctoral researcher will be recruited within the framework of the IDYLLE project (Impact of Lithosphere Dynamics and Basin Evolution on the Exploration of Energy Resources and Geological Potential) of the PEPR “Subsurface, bien commun”, funded by the French National Research Agency (ANR). This project involves the CNRS, BRGM, IFP Energies nouvelles (IFPen), the Universities of Toulouse, Montpellier, Lorraine, and the University of Pau and Pays de l'Adour. The IDYLLE project aims to understand the impact of lithospheric processes controlling heat, fluid, and gas transfers on the formation of resources such as natural hydrogen. This issue will be re-evaluated in the Aquitaine Basin and the northern Pyrenees.

Compensation and benefits

Compensation

from 3041 to 4216€ monthly gross salary

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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