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Mechanoluminescent Visualization of Crack Propagation for Joint Evaluation
Published on: January 6, 2023
El desgarro de la losa estancada se rompe
Masayuki Obayashi1, Junko Yoshimitsu, Yoshio Fukao
1Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, Yokosuka 237-0061, Japan. obayashi@jamstec.go.jp
Science (New York, N.Y.)
|May 30, 2009
Resumen
Las placas tectónicas subductoras debajo de Japón se están desgarrando en su unión. Este desgarro continuo de la losa ocurre a medida que las placas se doblan y aplanan sobre la discontinuidad de 660 kilómetros.
Área de la Ciencia:
- La geofísica es la geofísica.
- La tectónica es la tectónica.
- Sismología Sismología Sismología.
Sus antecedentes:
- Las placas de subducción en el Pacífico occidental, como las placas de Izu-Bonin y Japón, a menudo se estancan en la zona de transición del manto.
- Las propiedades mecánicas de estas losas estancadas son poco conocidas.
- Estas dos losas específicas forman una unión única bajo el suroeste de Japón.
Objetivo del estudio:
- Para investigar el comportamiento mecánico de las losas Izu-Bonin y Japón en su unión.
- Para determinar si las losas están sufriendo desgarros debido a restricciones geométricas.
- Para proporcionar evidencia de los procesos de desgarro de losas en curso.
Principales métodos:
- Análisis geométrico de la flexión y el aplanamiento de la losa.
- Presentación de tres líneas distintas de evidencia que apoyan el desgarro de la losa.
- Análisis de datos sísmicos (implicado).
Principales resultados:
- Las placas de Izu-Bonin y Japón están evidentemente desgarradas en su unión.
- El desgarro de la losa es una consecuencia de la flexión y el aplanamiento en la discontinuidad de 660 kilómetros.
- La evidencia apoya un proceso de desgarro activo y continuo.
Conclusiones:
- La litosfera oceánica subducida puede experimentar desgarros significativos en profundidad.
- Los factores geométricos juegan un papel crucial en la deformación de las losas de subducción.
- Los hallazgos ofrecen nuevos conocimientos sobre la dinámica de los procesos de la zona de transición del manto.
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