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Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
La datación de terremotos: una aplicación del conteo de átomos de carbono-14 para el recuento de átomos de carbono-14
Science (New York, N.Y.)
|March 18, 1983
Resumen
Los investigadores fecharon el carbón relacionado con el terremoto prehistórico de Utah usando el conteo de átomos de carbono-14. Esto proporciona nuevas estimaciones de edad para antiguos eventos sísmicos en la falla Wasatch, que van desde hace 7.800 a 9.000 años.
Área de la Ciencia:
- Geología Geología Geología.
- La paleosismología es la paleosismología.
- Las citas radiométricas.
Sus antecedentes:
- La falla Wasatch en Utah es una característica geológica significativa con una historia de terremotos prehistóricos.
- Comprender el momento de los eventos sísmicos pasados es crucial para la evaluación del peligro sísmico.
Objetivo del estudio:
- Para determinar las edades de los terremotos prehistóricos asociados con la falla Wasatch.
- Aplicar técnicas avanzadas de datación a muestras geológicas.
Principales métodos:
- Conteo directo de átomos de carbono-14 (14C) mediante el uso de un acelerador en tándem Van de Graaff.
- Datación radiométrica de muestras de carbón vegetal detrital del tamaño de miligramos de las capas del suelo.
Principales resultados:
- Se determinaron edades de 7,800, 8,800, y 9,000 años antes del presente para las capas de suelo vinculadas a terremotos prehistóricos.
- La datación arrojó una incertidumbre de +/- 600 años para cada determinación de edad.
Conclusiones:
- El estudio dató con éxito el carbón vegetal asociado con la actividad sísmica prehistórica en la falla Wasatch.
- Los hallazgos proporcionan valiosos datos cronológicos para comprender la historia sísmica de la región.
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