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Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Evidencia sísmica de cambios de fase olivina en las discontinuidades de 410 y 660 kilómetros
Sergei Lebedev1, Sébastien Chevrot, Rob D van der Hilst
1Department of Earth, Atmospheric, and Planetary Sciences, Room 54-512, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. sergei@quake.mit.edu
Science (New York, N.Y.)
|May 23, 2002
Resumen
Los datos sísmicos apoyan la teoría de que la zona de transición del manto es una zona de transición.
Área de la Ciencia:
- La geofísica es la geofísica.
- Física mineral Física de los minerales
Sus antecedentes:
- La zona de transición del manto (MTZ) se caracteriza por discontinuidades sísmicas a profundidades de 410 y 660 km.
- Se debate la causa de estas discontinuidades, específicamente si se deben a transformaciones de fase isoquímicas de la olivina.
Objetivo del estudio:
- Investigar el papel de las transformaciones de fase olivina en la definición de las discontinuidades sísmicas de la zona de transición del manto.
- Para conciliar las observaciones sísmicas con los datos de la física mineral.
Principales métodos:
- Análisis combinado de mediciones de ondas convertidas de Asia Oriental y Australia.
- Integración con datos de velocidad sísmica de estudios tomográficos regionales.
Principales resultados:
- Se observó una correlación entre el grosor de la MTZ y las variaciones de la velocidad de onda, consistente con las transformaciones estructurales de la olivina.
- Las pendientes de Clapeyron inferidas sismológicamente se alinean con las pendientes de Clapeyron mineralógicas para las transformaciones de spinel y postspinel de (Mg,Fe) 2SiO4.
Conclusiones:
- El estudio proporciona pruebas sólidas que apoyan las transformaciones de fase olivina como la causa de las discontinuidades sísmicas de MTZ.
- Los hallazgos concilian las observaciones geofísicas con los principios de la física de los minerales, mejorando nuestra comprensión de los procesos profundos de la Tierra.
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