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Concentración de calcio-41 en materiales terrestres: perspectivas para la datación de muestras del pleistoceno
Science (New York, N.Y.)
|May 8, 1987
Resumen
El calcio-41 (Ca-41) es prometedor para la datación radiométrica de muestras geológicas de hasta un millón de años. Los investigadores midieron las concentraciones de Ca-41 en huesos y piedra caliza, validando su potencial para la datación de fósiles del Pleistoceno y estudios geofísicos.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Las citas radiométricas.
- Ciencias nucleares Ciencias nucleares.
Sus antecedentes:
- El calcio-41 (Ca-41) es un isótopo cosmogénico con aplicaciones potenciales en la datación radiométrica.
- Investigaciones anteriores han sugerido Ca-41 para la datación de muestras geológicas dentro del rango de 10^5 a 10^6 años.
- La determinación de la concentración de Ca-41 en muestras terrestres es crucial para validar su uso como herramienta de datación.
Objetivo del estudio:
- Para determinar la concentración de calcio 41 cosmogénico en muestras naturales terrestres.
- Evaluar la viabilidad del uso del calcio-41 para la datación radiométrica de materiales geológicos.
- Para explorar las aplicaciones geofísicas de las mediciones de calcio-41.
Principales métodos:
- Se empleó la espectrometría de masas de acelerador de alta sensibilidad (AMS) para la medición precisa del Ca-41.
- Se realizó un enriquecimiento previo del calcio-41 utilizando un separador de isótopos para mejorar la sensibilidad de detección.
- Las mediciones se llevaron a cabo en muestras contemporáneas de hueso bovino y depósitos de piedra caliza.
Principales resultados:
- Se determinó con éxito la concentración de calcio-41 en muestras naturales.
- Las proporciones medidas de calcio-41 al calcio total oscilaron entre 2 x 10^-14 y 3 x 10^-15.
- Estas concentraciones se encuentran dentro de los límites detectables para aplicaciones de datación.
Conclusiones:
- El calcio-41 se puede cuantificar en muestras terrestres utilizando técnicas avanzadas de AMS.
- Los hallazgos apoyan el potencial del Ca-41 como una nueva herramienta de datación radiométrica para las épocas del Pleistoceno Medio y Tardío.
- Investigaciones adicionales pueden explorar la utilidad del Ca-41 en varios contextos de datación geofísica.
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