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Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
Edad del Holoceno del entierro de Yuha: determinaciones directas de radiocarbono por espectrometría de masas de
Nature
|March 4, 1984
Resumen
La nueva datación por radiocarbono del esqueleto de Yuha revela que tiene menos de 4.000 años. Esta edad del Holoceno contradice las afirmaciones anteriores de un origen mucho más antiguo, del Pleistoceno tardío para las primeras poblaciones humanas en el hemisferio occidental.
Área de la Ciencia:
- Arqueología Arqueología.
- Paleontología Paleontología.
- Las citas radiométricas.
Sus antecedentes:
- Se debate la llegada de poblaciones humanas al hemisferio occidental, con algunos sitios que desafían la línea de tiempo establecida de ~ 12,000 años de radiocarbono BP.
- El sitio de entierro de Yuha en California, con una antigüedad reclamada de más de 20,000 años BP, ha sido un punto focal en este debate.
Objetivo del estudio:
- Para determinar con precisión la edad del esqueleto del Homo sapiens sapiens Yuha.
- Para resolver las discrepancias entre los métodos de datación anteriores y el contexto arqueológico del entierro.
Principales métodos:
- La datación por radiocarbono (relación 14C/13C) utilizando un espectrómetro de masas de acelerador en tándem en múltiples fracciones orgánicas e inorgánicas del hueso del esqueleto.
- Análisis de los resultados anteriores de datación, incluidos los recubrimientos de caliche, el contexto cultural, la geomorfología y la racemicidad de aminoácidos.
Principales resultados:
- La datación por radiocarbono de seis fracciones químicas del esqueleto de Yuha consistentemente dio edades menores a 4.000 años de radiocarbono BP.
- Estos resultados indican fuertemente una edad del Holoceno para el esqueleto, lo que contradice las asignaciones de edad del Pleistoceno anteriores (19.000-23.000 años BP).
Conclusiones:
- El esqueleto de Yuha es de la edad del Holoceno, alineándose con su contexto cultural.
- Los hallazgos desafían la antigüedad propuesta del entierro de Yuha y sus implicaciones para la migración humana temprana en el hemisferio occidental.
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