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The 1 April 2014 Iquique, Chile, M w 8.1 earthquake rupture sequence
Author(s) -
Lay Thorne,
Yue Han,
Brodsky Emily E.,
An Chao
Publication year - 2014
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2014gl060238
Subject(s) - seismology , hypocenter , geology , aftershock , foreshock , seismic gap , seismic moment , thrust fault , intraplate earthquake , fault (geology) , induced seismicity , tectonics
On 1 April 2014, a great ( M w 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 × 10 21 N m with a fault dip of 18°, radiated seismic energy of 4.5–8.4 × 10 16 J, and static stress drop of ~2.5 MPa. Most of the 1877 gap remains unbroken and hazardous.