Dynamic earthquake triggering response tracks evolving unrest at Sierra Negra volcano, Galápagos Islands

Research at Sierra Negra volcano, Galápagos Islands, reveals that the intensity of dynamically triggered earthquakes increases with the stress state during volcanic inflation. The study demonstrates that as magma reservoir inflation elevates local stress, the response to dynamic strain perturbations intensifies, with seismicity rates rising in tandem with peak dynamic strain. Conversely, post-eruptive subsidence and reduced stress levels diminish this triggering effect, even at equivalent dynamic strains. This finding provides critical insights into the controls on dynamic earthquake triggering and suggests that monitoring seismic responses to dynamic stresses could serve as an indicator for volcanic unrest evolution.

Bell, A. F., Hernandez, S., McCloskey, J., Ruiz, M., LaFemina, P. C., Bean, C. J., & Möllhoff, M. (2021). Dynamic earthquake triggering response tracks evolving unrest at Sierra Negra volcano, Galápagos Islands. Science Advances, 7(39). https://doi.org/10.1126/sciadv.abh0894