Heterogeneity and anomalous critical indices in the aftershocks distribution of L Aquila earthquake

TL;DR

This study analyzes aftershock data from the L Aquila earthquake, revealing heterogeneity in seismic activity across regions through anomalous critical indices, indicating varied stress distribution and regional differences.

Contribution

It introduces the identification of regional heterogeneity and anomalous critical indices in aftershock distributions using standard statistical geophysical tools.

Findings

Heterogeneity in seismic activity across five sub-regions.

Identification of two anomalous sub-regions with distinct indices.

Variation in stress distribution and morphology among regions.

Abstract

The data analysis of aftershock events of L Aquila earthquake in Apennines following the main 6.3 Mw event of April 6, 2009 has been carried out by standard statistical geophysical tools. The results show the heterogeneity of seismic activity in five different geographical sub-regions indicated by anomalous critical indices of power law distributions: the exponents of the Omori law, the b values of Gutenberg-Richter magnitude-frequency distribution, and the distribution of waiting times. The heterogeneous distribution of dynamic stress and a different morphology in the five sub-regions has been found and two anomalous sub-regions have been identified.