28/06/2022

Earthquake statistical properties: an explanation for the distribution of magnitude and for the existence of aftershocks

Par François Petrelis (LPENS, Paris)

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 show that these properties result from  the spatial distribution of the stress field. This field can be described as a random curve for one-dimensional models and a random surface for two-dimensional models. Using this analogy, a series of predictions is made that includes the Gutenberg-Richter law and, for two-dimensional models, the existence of aftershocks and their temporal distribution following Omori's law.