La sismicité des zones continentales stables

Micro- and moderate seismicity in Stable Continental Regions

• Auteur / Autrice : Farzaneh Mohammadi
• Direction : Romain Jolivet
• Type : Projet de thèse
• Discipline(s) : Géosciences et géoingénierie
• Date : Inscription en doctorat le 01/09/2024
• Etablissement(s) : Université Paris sciences et lettres
• Ecole(s) doctorale(s) : École doctorale Géosciences, ressources naturelles et environnement
• Partenaire(s) de recherche : Laboratoire : Laboratoire de Géologie de l'Ecole Normale Supérieure
• Partenaire(s) de recherche : établissement opérateur d'inscription : Ecole normale supérieure

Mots clés

Mots clés libres

Régions continentales stables

Sismicité

Machine Learning

Stable continental regions

Seismicity

Machine Learning

Résumé

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The project involves building new catalogs of low-magnitude seismicity (microseismicity) in stable continental regions using recent machine-learning-based earthquake detection techniques. The catalogs will be used to constrain new models of the rheology of marginally deformed continental regions. While most earthquakes occur along rapidly deforming plate boundaries, continental interiors are less often struck by devastating earthquakes. Over the last centuries, multiple events have left scientists puzzled as to how could such earthquake occur as they do not follow the classic and now quite well accepted description of earthquakes as the response of a frictional interface to stress which more or less constantly increases with time. In continental interiors, no relative motion is observed across the faults responsible for those earthquakes, which by themselves indicate that elastic strain energy is available in the upper crust. In the iQuake project, we seek to explore the distribution of seismicity within such Stable Continental Regions using Machine Learning technologies on seismic and geodetic data (this PhD) and uncover the various stress perturbations acting on the continents at all temporal and spatial scales to test an elasto-plastic rheology implementing static fatigue.