Publications de François Xavier Thibault Passelègue

Frictional weakening leads to unconventional singularities during dynamic rupture propagation

Marie Estelle Solange Violay, Federica Paglialunga, Mathias Alexandre David Lebihain, François Xavier Thibault Passelègue

Earthquakes i.e. frictional ruptures, are commonly described by singular solutions of shear crack motions. These solutions assume a square root singularity order around the rupture tip and a constant shear stress value behind it, implying scale-independent ...

2024

Influence of Viscous Lubricant on Nucleation and Propagation of Frictional Ruptures

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Federica Paglialunga

Fluids are pervasive in the Earth's crust and saturate fractures and faults. The combination of fluids and gouge layers developing along faults can generate fluids of different viscosities. Such viscous fluids were found to influence the reactivation, fric ...

2023

Determination of Parameters Characteristic of Dynamic Weakening Mechanisms During Seismic Faulting in Cohesive Rocks

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Chiara Cornelio

While sliding at seismic slip-rates of ∼1 m/s, natural faults undergo an abrupt decrease of shear stress called dynamic weakening. Asperity-scale processes related to flash heating and weakening and, meso-scale (mm-cm) processes involving shear across the ...

AGU2022

On the scale dependence in the dynamics of frictional rupture: Constant fracture energy versus size-dependent breakdown work

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Mathias Alexandre David Lebihain, Federica Paglialunga, Fabian Barras

Potential energy stored during the inter-seismic period by tectonic loading around faults is released during earthquakes as radiated energy, frictional dissipation and fracture energy. The latter is of first importance since it is expected to control the n ...

2022

The influence of roughness on experimental fault mechanical behaviour and associated microseismicity

Brice Tanguy Alphonse Lecampion, Marie Estelle Solange Violay, Seyyedmaalek Momeni, François Xavier Thibault Passelègue, Carolina Giorgetti, Barnaby Padraig Fryer

Fault surfaces are rough at all scales, this significantly affecting fault-slip behaviour. However, roughness is only occasionally considered experimentally and then often in experiments imposing a low slip velocity, corresponding to the initiation stage o ...

2022

Brittle faulting of ductile rock induced by pore fluid pressure build‐up

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Corentin Jean-Marie Rémi Noël

Under upper crustal conditions, deformations are primarily brittle (i.e., localized) and accommodated by frictional mechanisms. At greater depth, deformations are ductile (i.e., distributed) and accommodated by crystal plasticity, diffusion mass transfer o ...

2021

Origin of the Co‐Seismic Variations of Elastic Properties in the Crust: Insight From the Laboratory

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Mateo Alejandro Acosta, Federica Paglialunga

Seismological observations highlighted that earthquakes are often followed by changes in elastic properties around the fault zone. Here, we studied the origin of these variations using stick-slip experiments on saw-cut granite samples presenting different ...

2021

Experimental plastic reactivation of pseudotachylyte‐filled shear zones

Marie Estelle Solange Violay, François Xavier Thibault Passelègue

Pseudotachylytes are fine‐grained fault rocks that solidify from melt that is produced in fault zones during earthquakes. Exposed sections of natural fault zones reveal evidence of post‐seismic plastic deformation (i.e. reactivation) of pseudotachylyte, wh ...

2021

Fault Stability Across the Seismogenic Zone

François Xavier Thibault Passelègue

Across the seismogenic zone, the transition from brittle to plastic deformation corresponds to a semibrittle regime where brittle fracturing and plastic flow coexist at high strength conditions. Thorough experimental investigations on brittle-plastic trans ...

AMER GEOPHYSICAL UNION2020

Initial effective stress controls the nature of earthquakes

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Fabian Barras

Modern geophysics highlights that the slip behaviour response of faults is variable in space and time and can result in slow or fast ruptures. However, the origin of this variation of the rupture velocity in nature as well as the physics behind it is still ...

Nature Research2020