Illuminating subduction zone rheological properties in the wake of a giant earthquake

Abstract

Deformation associated with plate convergence at subduction zones is accommodated by a complex system involving fault slip and viscoelastic flow. These processes have proven difficult to disentangle. The 2010 Mw 8.8 Maule earthquake occurred close to the Chilean coast within a dense network of continuously recording Global Positioning System stations, which provide a comprehensive history of surface strain. We use these data to assemble a detailed picture of a structurally controlled megathrust fault frictional patchwork and the three-dimensional rheological and time-dependent viscosity structure of the lower crust and upper mantle, all of which control the relative importance of afterslip and viscoelastic relaxation during postseismic deformation. These results enhance our understanding of subduction dynamics including the interplay of localized and distributed deformation during the subduction zone earthquake cycle.

Metadata

Authors/Creators:

Weiss, JR
Qiu, Q
Barbot, S
Wright, TJ https://orcid.org/0000-0001-8338-5935
Foster, JH
Saunders, A
Brooks, BA
Bevis, M
Kendrick, E
Ericksen, TL
Avery, J
Smalley Jr, R
Cimbaro, SR
Lenzano, LE
Barón, J
Báez, JC
Echalar, A

© 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY) (https://creativecommons.org/licenses/by/4.0/) This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Dates: