Mainshock-aftershock clustering in volcanic regions

Geophysical Research Letters



Earthquakes break their general Poissonean behavior through two types of seismic bursts: swarms and mainshock-aftershock sequences. The former is commonly thought to dominate in volcanic and geothermal regions, but aftershock production, including within swarms, is not well studied in volcanic regions. Here we compare mainshock-aftershock clustering in active volcanic regions in Japan to nearby nonvolcanic regions. We find that aftershock production is similar in both areas by two separate metrics: (1) Both volcanic and nonvolcanic regions have similar proportions of areas that cluster into mainshock-aftershock sequences. (2) Volcanic areas with mainshock-aftershock sequences have aftershock productivity at least as high as nonvolcanic regions. We also find that volcano-tectonic events that are precursors to an eruption are more common at volcanoes without mainshock-aftershock clusters than at volcanoes with well-defined mainshock-aftershock clusters. This last finding hints at a strategy to identify volcanic systems where cataloged earthquakes are good predictors of behavior.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Mainshock-aftershock clustering in volcanic regions
Series title Geophysical Research Letters
DOI 10.1002/2017GL075738
Volume 45
Issue 3
Year Published 2018
Language English
Publisher American Geophysical Union
Contributing office(s) Volcano Science Center
Description 9 p.
First page 1370
Last page 1378
Country Japan