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Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
El primer máximo glacial en América del Norte
Greg Balco1, Charles W Rovey, John O H Stone
1Quaternary Research Center and Department of Earth and Space Sciences, University of Washington, Seattle, WA 98915, USA. balcs@u.washington.edu
Science (New York, N.Y.)
|January 18, 2005
Resumen
Los científicos ahora pueden fechar antiguos depósitos glaciares utilizando núcleos producidos por rayos cósmicos. Este nuevo método, que utiliza berilio-10 y aluminio-26, permite la reconstrucción de las capas de hielo más antiguas a partir de pruebas terrestres.
Área de la Ciencia:
- Geología Geología Geología.
- Ciencia Cuaternaria La ciencia cuaternaria es la ciencia cuaternaria.
- Geocronología Geocronología.
Sus antecedentes:
- Los registros marinos indican al menos 50 avances de las capas de hielo del Plioceno-Pleistoceno.
- La reconstrucción de depósitos glaciares más antiguos a partir de pruebas terrestres es un desafío debido a las técnicas de datación limitadas.
Objetivo del estudio:
- Establecer un método confiable para la datación de depósitos glaciales más antiguos utilizando pruebas terrestres.
- Para permitir una reconstrucción precisa de la dinámica pasada de las capas de hielo.
Principales métodos:
- Utilizando nucleidos producidos por rayos cósmicos: berilio-10 (10Be) y aluminio-26 (26Al).
- La aplicación de estos núcleos para la datación de los sedimentos sobre los paleosolos.
Principales resultados:
- Demostró la eficacia de 10Be y 26Al en la datación de las sedes.
- Se ha fechado con éxito depósitos glaciales que antes no podían fecharse.
Conclusiones:
- La datación de nucleidos de rayos cósmicos proporciona una nueva herramienta para reconstruir la historia de la capa de hielo del Plioceno-Pleistoceno.
- Este método supera las limitaciones de las técnicas anteriores para la datación de depósitos glaciales más antiguos.
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