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Precursores sísmicos de las erupciones del Monte St. Helens en 1981 y 1982
Science (New York, N.Y.)
|September 30, 1983
Resumen
El monitoreo sísmico en el Monte St. Helens identificó seis categorías de eventos. Los terremotos de baja frecuencia, que aumentan antes de las erupciones, son clave para predecir la actividad volcánica.
Área de la Ciencia:
- Sismología Sismología Sismología.
- Volcanología Volcanología.
Sus antecedentes:
- El Monte St. Helens exhibe una actividad sísmica compleja.
- Comprender los tipos de eventos sísmicos es crucial para la evaluación del peligro volcánico.
Objetivo del estudio:
- Para categorizar los eventos sísmicos cerca del Monte St. Helens.
- Para identificar los precursores sísmicos de las erupciones volcánicas.
Principales métodos:
- Análisis de sismogramas de estaciones cercanas al Monte St. Helens.
- Clasificación de eventos sísmicos basados en frecuencia y profundidad.
Principales resultados:
- Se identificaron seis categorías de eventos sísmicos.
- Los terremotos de alta frecuencia ocurren a profundidades >4 km.
- Los terremotos de frecuencia media y baja ocurren a poca profundidad (<3 km) y aumentan antes de las erupciones.
- Los cambios de energía temporal en eventos de baja frecuencia predicen erupciones desde octubre de 1980.
- Los eventos de superficie emergentes de baja frecuencia (caídas de rocas, explosiones de gas) ocurren durante/después de las erupciones.
Conclusiones:
- La categorización de eventos sísmicos ayuda a comprender la actividad del Monte St. Helens.
- Los patrones de terremotos de baja frecuencia son predictores confiables de erupciones.
- El monitoreo de eventos sísmicos es vital para la gestión de riesgos volcánicos.
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