| Summary: | The island of Tierra del Fuego (Argentina-Chile) lies in aregion of intense seismic activity due to the interaction of theAntarctica, Scotia and South American tectonic plates. Twoseismotectonic zones in this region: the subduction trench insouthernmost Chile and the Magallanes-Fagnano fault, that crosses the island from east to west, represent a seismic hazard for the island population. Focusing on the Argentine sector of Tierra del Fuego, however, the greater threat comes from the Magallanes-Fagnano fault, which has generated seismic events in historical times of magnitude M=8. Tolhuin, a small population of 3000 inhabitants undergoing fast growth, is located 1 km from the trace of the Magallanes-Fagnano fault. Buildings in Tolhuin largely have not had seismic safety controls required by the INPRES (the Argentine seismic building code regulator). In addition, the urbanization of Tolhuin rests on a thick package of Quaternary glacigenic sediments with the potential for amplifying seismic vibrations by a factor of more than 2, judging from a simulation with EERA (Equivalent-linear Earthquake Analyses). Applying the Risk Assessment Tools for Diagnosis of Urban Areas against Seismic Disasters (RADIUS) methodology, supported by the United Nations, this study analyses the seismic vulnerability of constructions in Tolhuin under the effect of a Maximum Considered Earthquake of magnitude M=8.0. The results show the importance of considering the probable local amplification through site effects. This study constitutes a first effort to provide the Argentine province of Tierra del Fuego with cartographic and conceptual tools useful in planning urban growth taking into consideration seismic hazard. La Isla Grande de Tierra del Fuego (Argentina-Chile) está situada en un entorno de intensa actividad sísmica merced a lainteracción de las placas tectónicas Antártica, Scotia y Sudamericana. Dos zonas sismotectónicas en esta región: la fosa desubducción en el extremo austral de Chile y la falla Magallanes-Fagnano, que cruza ...
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