Missions

A post-doctoral position funded by the National Research Agency is open within the Laboratory of Planetology and Geosciences, CNRS UMR 6112, in Nantes, France. Our research aims to study the impact of heterogeneous heat flux at the core-mantle boundary (CMB) on dynamo regimes (dipole-dominated or reversing). Other goals include unravelling the current pattern of heat flux at the CMB, characterizing the Earth's magnetic field on millennial time scales, and identifying the necessary ingredients for Earth-like magnetic fields on millennial time scales in dynamo models.

Activities

The research activities are two-fold. First, the candidate will run numerical dynamo simulations with various combinations of main control parameters as well as different patterns and amplitudes of the heat flux on the outer boundary. The candidate will analyze these simulations to establish the dependence of the dynamo regime (dipole-dominated or reversing) on the pattern and amplitude of the heat flux at the outer boundary. Second, the candidate will define criteria for persistent characteristics of the geomagnetic field, including the South Atlantic anomaly, based on a statistically significant recurrence in a large set of archaeomagnetic and paleomagnetic field models.

Skills

The candidate must hold a doctorate in geosciences and/or planetology with knowledge of geomagnetism and core dynamics. Experience with numerical dynamo simulations and analysis/visualization of their output is required. In addition, experience with geomagnetic field models over different time scales (modern, historical, archaeomagnetic, paleomagnetic) is required. The candidate must have solid background in geophysics, mathematics and programming. In addition, the candidate must have good skills for working in a team as well as for producing peer-reviewed publications and activity reports.

Work Context

The Laboratoire de Planétologie et Géosciences (LPG) is a research lab of about a hundred people, under joint supervision of the CNRS and the University of Nantes, the University of Angers and Le Mans University. The person recruited will work on the Nantes site of the lab, on the Sciences campus of the University of Nantes. The lab's research is divided into three themes: Earth (in which this offer is positioned), Planets and Moons, and Coastal and Marine Systems. Placed under the hierarchical responsibility of the lab's Director, the recruited person will work in close collaboration with the leader and coordinator of the ANR DYRE-COMB project.

Constraints and risks

No particular constraints or risks.

Additional Information

The ANR DYRE-COMB project aims to establish the impact of heterogeneous heat flux on the core-mantle boundary (CMB) on dynamo regimes (dipole-dominated or reversing). Other objectives include understanding the current pattern CMB heat flux, the characterization of the Earth's magnetic field on millennial time scales and the identification of the necessary ingredients for Earth-like magnetic fields on millennial time scales in dynamo models. The project combines seismic tomography models, mantle convection simulations, numerical dynamo simulations and geomagnetic field models over different periods. The expected results include a set of realistic heat flux models at the CMB, criteria for 'Earth-like' magnetic field models on millennial time scales and revealing the dependence of the dynamo regimes on the amplitude and the pattern of the CMB heat flux.

The candidate will contribute to tasks 1, 4 and 5 of the ANR DYRE-COMB which concern numerical dynamo simulations and geomagnetic field models over different periods.