A repeating earthquake catalog for the Atacama Segment in North Chile (24.5°S-30.5°S)

Résumé fourni par la source

Repeating earthquakes are close to identical seismic events that recur on the same fault patch with consistent focal mechanisms. They can be used to estimate local fault slip and their magnitude-dependent recurrence intervals can serve to infer patterns of aseismically creeping zones at depth. We have constructed a long-term catalog of repeating earthquakes for the Atacama segment of the Chilean subduction zone. Using waveforms from approximately 60,000 earthquakes as templates, we performed GPU-based template matching on continuous data from 25 permanent seismic stations and one additional station with data from 1998 to 2024. The resulting catalog includes 4781 repeating events grouped into 1142 families, showing variability in size and behavior, from long-lasting sequences to short-term bursts. Several magnitude M5.7+ earthquakes significantly influenced the occurrence rates of nearby repeaters. The dataset is dominated by the 2015 Mw 8.3 Illapel megathrust earthquake. This catalog aims to support detailed analysis of rupture processes, source structures, and the spatiotemporal evolution of slow slip at depth. The production and reporting style are similar to a previous article by Folesky et al., 2025 on the adjacent northern Chile repeater catalog.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.