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El desplazamiento de Moho a través del margen norte de la meseta tibetana
1Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|August 26, 1998
Resumen
Las llegadas anómalas de ondas sísmicas revelan un desplazamiento significativo de Moho debajo de la meseta tibetana. Este límite agudo de la corteza sugiere una corteza tibetana débil que responde a las fuerzas tectónicas.
Área de la Ciencia:
- La geofísica es la geofísica.
- Sismología Sismología.
- La tectónica es la tectónica.
Sus antecedentes:
- Las llegadas de ondas P telesísmicas pueden ser distorsionadas por la heterogeneidad de la corteza.
- Comprender la estructura de la corteza es clave para descifrar los procesos tectónicos.
Objetivo del estudio:
- Para investigar las llegadas anómalas de ondas sísmicas cerca de la meseta tibetana.
- Para modelar la estructura subyacente de la corteza responsable de la distorsión de la forma de onda.
Principales métodos:
- Análisis de las llegadas anómalas de ondas P telesísmicas de doble pulso.
- Modelado de tres componentes de los datos sísmicos.
- Investigación de la dependencia azimutal de la distorsión de la forma de onda.
Principales resultados:
- Se observaron llegadas anómalas de ondas P que indican la heterogeneidad de la corteza del lado receptor.
- Se identificó un desplazamiento de Moho de 15 a 20 kilómetros en un estrecho rango lateral (<5 km).
- Este desplazamiento separa la gruesa corteza de la meseta tibetana de la corteza de la cuenca de Qaidam.
Conclusiones:
- El agudo desplazamiento de Moho implica una corteza débil de la meseta tibetana.
- La corteza tibetana se espesa verticalmente debido a la penetración de la India hacia el norte.
- Una fuerte corteza de la cuenca de Qaidam actúa como una barrera norte para este engrosamiento.
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