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The Iquique earthquake sequence of April 2014: Bayesian modeling accounting for prediction uncertainty

Zacharie Duputel·Junle Jiang·Romain Jolivet·Mark Simons·Luis Rivera·Jean-Paul Ampuero·Bryan Riel·Susan E Owen·Angelyn W Moore·Sergey V Samsonov·Francisco Ortega Culaciati·Sarah E. Minson
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Abstract

The subduction zone in northern Chile is a well-identified seismic gap that last ruptured in 1877. On 1 April 2014, this region was struck by a large earthquake following a two week long series of foreshocks. This study combines a wide range of observations, including geodetic, tsunami, and seismic data, to produce a reliable kinematic slip model of the M w =8.1 main shock and a static slip model of the M w =7.7 aftershock. We use a novel Bayesian modeling approach that accounts for uncertainty in the Green's functions, both static and dynamic, while avoiding nonphysical regularization. The results reveal a sharp slip zone, more compact than previously thought, located downdip of the foreshock sequence and updip of high-frequency sources inferred by back-projection analysis. Both the main shock and the M w =7.7 aftershock did not rupture to the trench and left most of the seismic gap unbroken, leaving the possibility of a future large earthquake in the region.

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Geophysical Research LettersArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: -24° to -16° latitude; -73° to -69° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Zacharie Duputel, Junle Jiang, Romain Jolivet, Mark Simons, Luis Rivera, Jean-Paul Ampuero, Bryan Riel, Susan E Owen, Angelyn W Moore, Sergey V Samsonov, Francisco Ortega Culaciati, Sarah E. Minson. 2015-10-03. The Iquique earthquake sequence of April 2014: Bayesian modeling accounting for prediction uncertainty. https://doi.org/10.1002/2015gl065402

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