HR: 10:20h
AN: OS21D-01 [PDF]
TI: Vulnerability Assessment and Prevention Measures for Tsunami
Flooding of Coastal Areas in Mexico
AU: * Farreras, S F
EM: sfarrera@cicese.mx
AF: Oceanology Division, CICESE Research Center of Mexico, P.O. Box 434844, San Diego, CA 92143-4844 United States
AU: Ortiz, M
EM: ortizf@cicese.mx
AF: Oceanology Division, CICESE Research Center of Mexico, P.O. Box 434844, San Diego, CA 92143-4844 United States
AB:
The Middle-America Trench subduction zone adjacent to the southwestern coast of Mexico accounts for a consistent and regular
history of locally destructive tsunamis generated by large earthquakes. 3 and 5 meters are the maximum wave heights
representative of low and middle risk for the most frequent of these tsunamis. This coast is the site of industrial ports,
tourist resorts and urban communities. The main industrial port, located on the sand shoals of a river delta, has two steel
mill plants, a fertilizer factory, container, metal and mineral docks, grain storage silos, and a fuel oil terminal.
An important element for the vulnerability assessment is the determination of probable tsunami wave elevations and expected
inundation limits. The two cases mentioned above were computer simulated. An ocean water disturbance produced by a sea-floor
earthquake was assumed. Linear wave theory for the deep ocean, and non-linear one for the near shore and interaction with the
coast, were used. Non-fixed boundaries were considered. The equations were solved by a finite-difference algorithm for
interconnected grids of different sizes. The model was validated comparing the results with sea level data, run-up and
flooding extensions measured from past tsunamis.
Results of the numerical simulations show maximum water levels and boundaries of the inundation areas under threat.
Inundation maps were produced. Vulnerability assessments for two cases, an urban settlement and the main industrial port, are
described. A low risk event will produce slight damage, railroad tracks destroyed, access bridges washed out, and ledges of
sand removed or deposited on the beaches; and a middle risk event will produce major and extensive damage to the
installations and danger to life. Recommendations include the relocation of urban settlements, installations and services,
and the establishment of evacuation routes and emergency shelters.
DE: 4564 Tsunamis and storm surges
DE: 7223 Seismic hazard assessment and prediction
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting