On April 1st 2007 a large earthquake of magnitude 8.1 occurred offshore Solomon Islands at 20:40:38 UTC. Numerical simulations of the tsunami event caused by the earthquake have been performed to compare the results obtained by the SWAN-JRC code (Annunziato, 2007), the TUNAMI (Imamura, 1996) and the HYFLUX2 (Franchello, 2008). The analysis conducted using these numerical simulations were also compared with NOAA-MOST code unit source results.
The tsunami event has been simulated considering several options for the seismological parameters as input data: Finite Fault Model (USGS, 2007), the Centroid Moment Tensor fault model and other mechanisms derived from the field survey analysis (Tanioka model).
The main aim of this study is to assess how the different fault models affect the overall results and to perform a comparison among the various codes in the wave propagation phase. Another objective of this study is to use HYFLUX2 code to calculate inundation and compare the simulation results with site field measurements.
The study has been separated into two main parts. The first one represents the collection of information about focal mechanisms: the fault analysis in chapter 4 covers one of the main aims of this research where different fault scenarios have been tested using published field data. The second part describes the different calculations that have been performed in order to analyze the response of the wave propagation models to various fault deformation models. For the inundation assessment, more detailed calculations at 300m grid size resolutions have been performed, using the fault model that best represent the deformation.
The calculations in the propagation assessment subsection were performed using: SWAN-JRC, HYFLUX2, TUNAMI-N2 and NOAA-MOST code. In the inundation assessment the HYFLUX2 numerical code, initialized with the Tanioka fault model was used.
The deformation comparison with field measured data shows that none of the ¿quick¿ fault mechanism was able to estimate correctly the measured value. The best model is the empirical model by Tanioka which was obtained by trying to reproduce the measured value.
From the published fault mechanism the one that shows a better correlation with measurements is the simple cosinuosoidal model. Results of simulations done with 300 m grid, show a maximum wave height of 7.5 m. Though the maximum run up reported was 10 m in Tapurai site, Simbi Island, the simulation results are encouraging.
ZAMORA Natalia;
FRANCHELLO Giovanni;
ANNUNZIATO Alessandro;
2011-07-27
Publications Office of the European Union
JRC62983
978-92-79-19851-9 (print),
978-92-79-19852-6,
1018-5593 (print),
1831-9424,
EUR 24783 EN,
OP LB-NA-24783-EN-C (print),
OP LB-NA-24783-EN-N,
https://publications.jrc.ec.europa.eu/repository/handle/JRC62983,
10.2788/859 (print),
10.2788/86267,
