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Zonificación de isótopos de oxígeno en el granate
Science (New York, N.Y.)
|October 18, 1991
Resumen
La zonificación de isótopos de oxígeno en granates metamórficos revela las reacciones de infiltración y deshidratación de fluidos durante el metamorfismo. Estos cambios en los valores de los isótopos de oxígeno (delta(18) O) proporcionan información sobre los procesos geológicos.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Geología de Isótopos Geología de Isótopos.
- Petrología Metamórfica.
Sus antecedentes:
- El granate es un mineral clave en las rocas metamórficas, preservando información sobre las condiciones P-T.
- El análisis de isótopos de oxígeno es una herramienta poderosa para rastrear las interacciones fluido-roca.
Objetivo del estudio:
- Para investigar la zonificación de isótopos de oxígeno dentro de granates metamórficos.
- Para comprender la influencia de los procesos metamórficos en la geoquímica del granate.
Principales métodos:
- Análisis con sonda láser de isótopos estables de los isótopos de oxígeno (delta) 18O).
- Examen de cuatro granadas de Vermont y Utah.
Principales resultados:
- Se observó zonificación concentrada de isótopos de oxígeno (delta(18) O) en todos los granates examinados.
- Los granates metamórficos regionales mostraron las mayores variaciones (hasta 3 por mil desde el núcleo hasta el borde).
Conclusiones:
- La zonificación de isótopos de oxígeno en granates refleja cambios en el delta rocoso durante el crecimiento.
- La infiltración de fluidos y las reacciones de deshidratación son los principales impulsores de estas variaciones isotópicas durante el metamorfismo.
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