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Vidrio de olivino producido por choque: primera observación
Science (New York, N.Y.)
|July 29, 1977
Resumen
La deformación por choque del peridoto a altas presiones (56 GPa) creó el primer vidrio de olivino observado. Este descubrimiento sugiere que los eventos de choque por encima de 50-55 GPa pueden formar vidrio en olivinas naturales.
Área de la Ciencia:
- Geología Geología Geología.
- Ciencia de los materiales Ciencia de los materiales.
- Física de los minerales Física de los minerales
Sus antecedentes:
- El peridoto, una variedad de calidad de gema del mineral olivino, es un componente importante del manto superior de la Tierra.
- Comprender el comportamiento de la olivina en condiciones extremas es crucial para la ciencia planetaria y la geofísica.
Objetivo del estudio:
- Para investigar los cambios microestructurales en el peridoto natural sometido a deformación de choque experimental.
- Para identificar las condiciones de formación y las características de cualquier fase amorfa producida por el choque.
Principales métodos:
- Se utilizó microscopía electrónica de transmisión (TEM) para examinar un solo cristal de peridoto natural.
- La muestra de peridoto fue experimentalmente deformada por choque a una presión máxima de aproximadamente 56 GPa.
Principales resultados:
- Se observaron zonas amorfas, identificadas como vidrio olivino, dentro de las regiones cristalinas del peridoto impactado.
- La formación de vidrio estaba estrechamente asociada con áreas que exhibían una alta densidad de dislocaciones enredadas.
- El estudio proporciona la primera observación reportada de vidrio de olivina inducido por choque.
Conclusiones:
- El vidrio de olivina puede formarse en olivinas naturales sometidas a presiones de choque que exceden aproximadamente 50-55 GPa.
- Otros estudios TEM de olivinas naturalmente golpeadas podrían confirmar la presencia generalizada de vidrio inducido por choque.
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