Annuaire

Thesis topic: Micro-porosity formation in viscously deformed rocks (supervised by Jacques Précigout, Cécile Prigent, Laurent Arbaret, Laura Airaghi)

Thesis description: At crustal shear zones, where rocks are deformed viscously, it is not uncommon to find micro-porosity in mylonites. This porosity is seen at grain and sub-grain boundaries in both poly- and mono-mineralic shear bands. The pores may facilitate the movement of fluids through shear zones, and potentially facilitate ore deposit formation. Furthermore, porosity and the associated fluid pressure may cause embrittlement below the seismogenic zone, leading to brittle failure and earthquakes.
Over the years since first identification, micro-porosity has been subjected to various hypotheses aimed at describing its formation. However, within the broader context, no single hypothesis offers a complete description of porosity formation. The goal of my project is to study, through natural samples and experimental analogues, mylonites which contain micro-porosity and try to determine how micro-porosity may have formed, specifically within mono-mineralic (quartz and calcite) rocks.