Earthquake statistical properties: an explanation for the distribution of magnitude and for the existence of aftershocks
15/10/2024
IPGP - Îlot Cuvier
14:00
Séminaires de Sismologie
Salle 310
François Pétrélis
Laboratoire de Physique de l'Ecole Normale Supérieure
Earthquakes in nature follow several statistical properties. In particular, the distribution of energy released by an earthquake (Gutenberg-Richter's law) and the frequency of aftershocks after a large event (Omori's law) are both power-laws.
By studying several earthquake models, we have shown that the Gutenberg-Richter law results from the spatial distribution of the stress field. This field is self-similar at large scale and for two dimensionnal systems can be modelled as a random surface. Using this analogy, a series of predictions is made that includes the Gutenberg-Richter law and the value of its exponent (so called b-value) together with the existence of aftershocks and their temporal distribution following Omori's law.