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Edades terrestres de cuatro meteoritos de Allan Hills: consecuencias para el hielo antártico
Science (New York, N.Y.)
|February 2, 1979
Resumen
Las edades terrestres de los meteoritos revelan que la capa de hielo de la Antártida tiene más de 1,54 millones de años. La recolección de meteoritos en Allan Hills probablemente comenzó hace entre 30.000 y 300.000 años.
Área de la Ciencia:
- Cosmoquímica y Ciencias Planetarias.
- Geocronología Geocronología.
- Glaciología glaciología.
Sus antecedentes:
- Comprender las edades terrestres de los meteoritos proporciona información sobre la historia ambiental de la Tierra.
- La región de Allan Hills en la Antártida es un sitio conocido para la recuperación de meteoritos.
- La datación de los meteoritos ayuda a establecer edades mínimas para la estabilidad de la capa de hielo.
Objetivo del estudio:
- Para determinar las edades terrestres de los meteoritos de Allan Hills.
- Para inferir la edad mínima de la capa de hielo de la Antártida.
- Para estimar el inicio de la acumulación de meteoritos en Allan Hills.
Principales métodos:
- Datación radiométrica de muestras de meteoritos.
- Análisis de núcleos cosmogénicos para determinar la duración de la exposición terrestre.
Principales resultados:
- Tres meteoritos de Allan Hills tienen edades terrestres entre 3 x 10^4 y 3 x 10^5 años.
- Un meteorito tiene una edad terrestre de (1.54 ± 0.14) x 10^6 años.
- La capa de hielo de la Antártida tiene más de 1,54 millones de años.
Conclusiones:
- La edad mínima de la capa de hielo antártica se establece en más de 1,54 millones de años.
- La acumulación de meteoritos en Allan Hills probablemente comenzó hace entre 3 x 10^4 y 3 x 10^5 años.
- Estos hallazgos contribuyen a reconstruir la historia glacial de la Antártida y los eventos de caída de meteoritos.
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