Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 27, 2007 | Published
Journal Article Open

Near-field propagation of tsunamis from megathrust earthquakes


We investigate controls on tsunami generation and propagation in the near-field of great megathrust earthquakes using a series of numerical simulations of subduction and tsunamigenesis on the Sumatran forearc. The Sunda megathrust here is advanced in its seismic cycle and may be ready for another great earthquake. We calculate the seafloor displacements and tsunami wave heights for about 100 complex earthquake ruptures whose synthesis was informed by reference to geodetic and stress accumulation studies. Remarkably, results show that, for any near-field location: (1) the timing of tsunami inundation is independent of slip-distribution on the earthquake or even of its magnitude, and (2) the maximum wave height is directly proportional to the vertical coseismic displacement experienced at that location. Both observations are explained by the dominance of long wavelength crustal flexure in near-field tsunamigenesis. The results show, for the first time, that a single estimate of vertical coseismic displacement might provide a reliable short-term forecast of the maximum height of tsunami waves.

Additional Information

© 2007 American Geophysical Union. Received 25 April 2007; accepted 25 June 2007; published 27 July 2007. We thank Rory Quinn for assistance in the bathymetric modelling, Spina Cianetti for assistance in construction of the finite element model of subduction, and Chris Bean for constructive criticism of the manuscript. The Landsat ETM+ data is used courtesy of the Global Land Cover Facility (http://www.landcover.org). We acknowledge financial support from the Natural Environmental Research Council.

Attached Files

Published - McCloskey2007p14316_Geophys_Res_Lett.pdf


Files (374.2 kB)
Name Size Download all
374.2 kB Preview Download

Additional details

August 22, 2023
October 21, 2023