%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Villegas-Lanza, J. C.
%A Nocquet, Jean-Mathieu
%A Rolandone, F.
%A Vallée, Martin
%A Tavera, H.
%A Bondoux, Francis
%A Tran, T.
%A Martin, Xavier
%A Chlieh, Mohamed
%T A mixed seismic-aseismic stress release episode in the Andean subduction zone
%D 2016
%L fdi:010066173
%G ENG
%J Nature Geoscience
%@ 1752-0894
%K PEROU ; ANDES
%M ISI:000369324600021
%N 2
%P 150-154
%R 10.1038/ngeo2620
%U https://www.documentation.ird.fr/hor/fdi:010066173
%> https://www.documentation.ird.fr/intranet/publi/2016/03/010066173.pdf
%V 9
%W Horizon (IRD)
%X In subduction zones, stress is released by earthquakes and transient aseismic slip. The latter falls into two categories: slow slip and afterslip. Slow-slip events emerge spontaneously during the interseismic phase, and show a progressive acceleration of slip with a negligible contribution of synchronous tremors or microseismicity to the energy, or moment release(1-12). In contrast, afterslip occurs immediately after large and moderate earthquakes, decelerates over time, and releases between 20 and 400% of the moment released by the preceding earthquake(13-18). Here we use seismic and GPS data to identify transient aseismic slip that does not fit into either of these categories. We document a seismic-aseismic slip sequence which occurred at shallow depths along a weakly coupled part of the Andean subduction zone(19) in northern Peru and lasted seven months. The sequence generated several moderate earthquakes that together account for about 25% of the total moment released during the full sequence, equivalent to magnitude 6.7. Transient slip immediately followed two of the earthquakes, with slip slowing at a logarithmic rate. Considered separately, the moment released by transient slip following the second earthquake was more than 1,000% of the moment released during the earthquake itself, a value incompatible with classical models of afterslip. Synchronous seismic swarms and aseismic slipmay therefore definea stress-release process that is distinct from slow-slip events and afterslip.
%$ 066