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Los superciclos de terremotos se deducen de los cambios en el nivel del mar registrados en los corales de Sumatra
Kerry Sieh1, Danny H Natawidjaja, Aron J Meltzner
1Tectonics Observatory, California Institute of Technology, Pasadena, CA 91125, USA. sieh@ntu.edu.sg
Science (New York, N.Y.)
|December 17, 2008
Resumen
Los registros de coral de las islas Mentawai revelan que el megatrust Sunda genera grandes terremotos cada ~ 200 años. El terremoto de 2007 es el primero de varios fallos parciales anticipados en esta zona sísmica.
Área de la Ciencia:
- Geología Geología Geología.
- La paleosismología es la paleosismología.
- La tectónica es la tectónica.
Sus antecedentes:
- El megatrust de Sunda es una importante característica tectónica responsable de una actividad sísmica significativa en Indonesia.
- Comprender el intervalo de repetición de los grandes terremotos es crucial para la evaluación del peligro sísmico en la región.
Objetivo del estudio:
- Para reconstruir la historia de los grandes terremotos a lo largo de la sección de Mentawai de la Sunda megathrust.
- Para evaluar el potencial sísmico y el comportamiento de ruptura futuro de este segmento.
Principales métodos:
- Análisis de los registros de cambio relativo del nivel del mar conservados en las formaciones coralinas.
- Reconstrucción paleosísmica basada en datos geocronológicos de muestras de coral.
Principales resultados:
- La evidencia sugiere un intervalo de repetición de aproximadamente 200 años para los grandes terremotos en los últimos 700 años.
- El terremoto de magnitud 8.4 de 2007 se identifica como el evento inicial en una potencial serie de rupturas.
Conclusiones:
- La sección de Mentawai del megatrust Sunda exhibe un patrón consistente de generación de grandes terremotos.
- El terremoto de 2007 probablemente marca el comienzo de una secuencia de fallas parciales de varias décadas, lo que requiere un monitoreo continuo y una evaluación de riesgos.
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