TY  - JOUR
A1  - Melnick, Daniel
A1  - Moreno, Marcos
A1  - Quinteros, Javier
A1  - Carlos Baez, Juan
A1  - Deng, Zhiguo
A1  - Li, Shaoyang
A1  - Oncken, Onno
T1  - The super-interseismic phase of the megathrust earthquake cycle in Chile
JF  - Geophysical research letters
N2  - Along a subduction zone, great megathrust earthquakes recur either after long seismic gaps lasting several decades to centuries or over much shorter periods lasting hours to a few years when cascading successions of earthquakes rupture nearby segments of the fault. We analyze a decade of continuous Global Positioning System observations along the South American continent to estimate changes in deformation rates between the 2010 Maule (M8.8) and 2015 Illapel (M8.3) Chilean earthquakes. We find that surface velocities increased after the 2010 earthquake, in response to continental-scale viscoelastic mantle relaxation and to regional-scale increased degree of interplate locking. We propose that increased locking occurs transiently during a super-interseismic phase in segments adjacent to a megathrust rupture, responding to bending of both plates caused by coseismic slip and subsequent afterslip. Enhanced strain rates during a super-interseismic phase may therefore bring a megathrust segment closer to failure and possibly triggered the 2015 event.
KW  - megathrust
KW  - earthquake
KW  - cycle
KW  - Chile
Y1  - 2017
U6  - https://doi.org/10.1002/2016GL071845
SN  - 0094-8276
SN  - 1944-8007
VL  - 44
IS  - 2
SP  - 784
EP  - 791
PB  - American Geophysical Union
CY  - Washington
ER  -