Verifying the magnitude dependence in earthquake occurrence

TL;DR

This study investigates whether a dependence exists between earthquake magnitudes in triggering sequences, using synthetic and real earthquake data, and finds evidence against the hypothesis of magnitude correlation.

Contribution

The paper provides a comprehensive analysis combining synthetic models and high-resolution data to test the magnitude dependence hypothesis in earthquake triggering.

Findings

Magnitude correlation hypothesis can be rejected.

Synthetic data supports independence of earthquake magnitudes.

Real earthquake data analysis shows no significant magnitude dependence.

Abstract

The existence of magnitude dependence in earthquake triggering has been reported. Such a correlation is linked to the issue of seismic predictability and remains under intense debate whether it is physical or is caused by incomplete data due to short-term aftershocks missing. Working firstly with a synthetic catalogue generated by a numerical model that capture most statistical features of earthquakes and then with an high-resolution earthquake catalogue for the Amatrice-Norcia (2016) sequence in Italy, where for the latter case we employ the stochastic declustering method to reconstruct the family tree among seismic events and limit our analysis to events above the magnitude of completeness, we found that the hypothesis of magnitude correlation can be rejected.