The 1 April 2014 Iquique, Chile, Mw 8.1 earthquake rupture sequence
Abstract
On 1 April 2014, a great (Mw 8.1) interplate thrust earthquake ruptured in the northern portion of the 1877 earthquake seismic gap in northern Chile. The sequence commenced on 16 March 2014 with a magnitude 6.7 thrust event, followed by thrust-faulting aftershocks that migrated northward ~40 km over 2 weeks to near the main shock hypocenter. Guided by short-period teleseismic P wave backprojections and inversion of deepwater tsunami wave recordings, a finite-fault inversion of teleseismic P and SH waves using a geometry consistent with long-period seismic waves resolves a spatially compact large-slip (~2-6.7 m) zone located ~30 km downdip and ~30 km along-strike south of the hypocenter, downdip of the foreshock sequence. The main shock seismic moment is 1.7 × 1021 N m with a fault dip of 18°, radiated seismic energy of 4.5-8.4 × 1016 J, and static stress drop of ~2.5 MPa. Most of the 1877 gap remains unbroken and hazardous.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- June 2014
- DOI:
- 10.1002/2014GL060238
- Bibcode:
- 2014GeoRL..41.3818L
- Keywords:
-
- 2014 Iquique earthquake;
- 1877 Chile seismic gap;
- rupture process;
- seismic source model