Artículo de revista
Coseismic seafloor deformation in the trench region during the Mw8.8 Maule megathrust earthquake
Fecha
2017Registro en:
Scientific Reports, | 7:45918
20452322
10.1038/srep45918
Autor
Maksymowicz, A.
Chadwell, C. D.
Ruiz, J.
Tréhu, A. M.
Contreras Reyes, E.
Weinrebe, W.
Díaz Naveas, J.
Gibson, J. C.
Lonsdale, P.
Tryon, M. D.
Institución
Resumen
The Mw 8.8 megathrust earthquake that occurred on 27 February 2010 offshore the Maule region of
central Chile triggered a destructive tsunami. Whether the earthquake rupture extended to the shallow
part of the plate boundary near the trench remains controversial. The up-dip limit of rupture during
large subduction zone earthquakes has important implications for tsunami generation and for the
rheological behavior of the sedimentary prism in accretionary margins. However, in general, the slip
models derived from tsunami wave modeling and seismological data are poorly constrained by direct
seafloor geodetic observations. We difference swath bathymetric data acquired across the trench in
2008, 2011 and 2012 and find ~3–5 m of uplift of the seafloor landward of the deformation front, at the
eastern edge of the trench. Modeling suggests this is compatible with slip extending seaward, at least,
to within ~6 km of the deformation front. After the Mw 9.0 Tohoku-oki earthquake, this result for the
Maule earthquake represents only the second time that repeated bathymetric data has been used to
detect the deformation following megathrust earthquakes, providing methodological guidelines for
this relatively inexpensive way of obtaining seafloor geodetic data across subduction zone.