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La acumulación de cloro-36 cosmogénico en las rocas: un método para la exposición superficial
Science (New York, N.Y.)
|January 3, 1986
Resumen
La acumulación de cloro-36 en las rocas ofrece un nuevo geocronómetro. Este método mide el tiempo de exposición superficial de las rocas volcánicas y las formas de relieve, fechando las características de 1.000 a 1.000.000 años.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- El núcleo cosmogénico data de los núcleos cósmicos.
- Geocronología Geocronología.
Sus antecedentes:
- Las interacciones de los rayos cósmicos con los minerales producen nucleidos cosmogénicos.
- El cloro-36 (36Cl) se acumula en las rocas de la superficie de la Tierra.
- El cloruro estable (Cl−) es un elemento común en las rocas.
Objetivo del estudio:
- Para evaluar la relación entre 36Cl y Cl estable como un geocronómetro.
- Determinar la viabilidad del uso de 36Cl para la datación de rocas volcánicas jóvenes y características geomórficas.
Principales métodos:
- Medición de las concentraciones de 36Cl en rocas volcánicas de edades conocidas.
- El cálculo predijo la producción de 36Cl basado en la composición de la roca y el flujo de rayos cósmicos.
- Analizando la relación entre el 36Cl y el Cl estable.
Principales resultados:
- Se encontró una buena concordancia entre el 36Cl medido en rocas volcánicas fechadas y la producción calculada.
- La relación 36Cl/Cl muestra potencial como un geocronómetro confiable.
- El método es aplicable a la exposición superficial.
Conclusiones:
- La relación 36Cl/Cl es un geocronómetro viable para la datación de la exposición superficial.
- Este método puede datar rocas volcánicas jóvenes y características geomórficas.
- El rango efectivo de datación es de 103 a 106 años.
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