Missions

In the context of MUSH-OCEAN, this postdoctoral project will focus on quantifying the kinetics of cooling rates and the microtextural maturation of plutonic rocks related to slow cooling.

Activités

The main tools will be those of diffusion chronometry (e.g. Ca in Ol1), and the use of dihedral angles in solidified plutonic rocks. A key objective will be to improve current approaches to quantify those cooling rates by providing 1/ a finite difference model to fit Ca profiles in olivine and calculate associated cooling rates, 2/ an analysis of uncertainty propagation for these models, and 3/ a global unified database of existing data that could be used together with the new numerical model to compare cooling rates in the various available sections of oceanic crust. These, together with new data from natural samples from selected areas, will be used to improve our understanding of the formation and evolution of oceanic crust. Samples from several drilled and dredged areas are available in the CRPG collection (EPR: Hess Deep, MAR: Atlantis Massif, SWIR: Atlantis Bank, Oman ophiolite, and several others). These new cooling rate results will be complemented by a detailed microstructural study focusing mainly on grain and grain boundary shapes (aspect ratio & dihedral angles) to unravel the unique message recorded in plutonic rock textures.

Compétences

The postdoctoral fellow will work with Dr Lydéric France at CRPG, and will collaborate with Jean-Marc Montel (CRPG), David Jousselin (CRPG), and Marian Holness (Cambridge, UK). We are looking for highly motivated candidates with demonstrated interest in numerical models and/or diffusion chronometry models. The project involves petrography (dihedral angle measurements), so candidates with an interest in this domain are expected, but no specific background is expected as learning this approach will be part of the project.

Contexte de travail

The Centre de Recherches Pétrographiques et Géochimiques (CRPG, UMR 7358), located in Vandoeuvre-lès-Nancy in the Grand Est region of France, is a geosciences research laboratory associated with both the Centre National de la Recherche Scientifique (CNRS) and the Université de Lorraine (UL) (https://crpg.univ-lorraine.fr/).

Contraintes et risques

n.a.