Publication Date:
2019
Description:
A Mw 7.2 earthquake struck the south flank of Kilauea, Hawaii, on May 4 2018, following a period of volcanic unrest. To investigate its relationship with the stress changes induced by prior tectonic and magmatic activity, we model the co‐seismic slip distribution, pre‐intrusion deformation and dike intrusion using geodetic, seismic and tsunami observations. The décollement beneath the south‐flank was creeping seaward by ~25 cm/yr. Diking started on April 20 and lead to fissures eruption on May 3. The magmatic activity and creep resulted in an on‐shore U‐shaped zone of stress unloading, fringed by an off‐shore zone of stress build up which apparently guided the 2018 rupture. It takes only 20 to 35 years at the pre‐intrusion rate to accumulate a moment deficit equivalent to the moment that was released in 2018. This event falls short of balancing the moment budget since the 1975, Mw 7.7 earthquake.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics
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