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Geoquímica: ¿qué tan bien pueden los isótopos de Pb fechar la formación del núcleo?
1Department of Earth Sciences, Laurentian University, Sudbury, Ontario P31 6B5, Canada.
Nature
|November 3, 2006
Resumen
La formación del núcleo planetario probablemente ocurrió rápidamente en 35 millones de años, desafiando los modelos que sugieren un proceso prolongado de dos etapas. Un nuevo análisis de los datos de isótopos de plomo apoya la temprana acreción y diferenciación de la Tierra.
Área de la Ciencia:
- Geoquímica y Ciencias Planetarias: Investiga el tiempo y los mecanismos de la formación y acreción del núcleo planetario.
Sus antecedentes:
- Los modelos de la historia temprana de la Tierra se basan en la comprensión de las escalas de tiempo de formación del núcleo.
- Estudios anteriores sugirieron una formación de núcleos en dos etapas basada en cronómetros de tungsteno (W) y plomo (Pb), lo que implicaba un proceso prolongado.
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