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Un marco cronológico para el Cuaternario británico basado en la opercula de Bitinia
Kirsty E H Penkman1, Richard C Preece, David R Bridgland
1BioArCh, Department of Archaeology, University of York, York YO10 5DD, UK. kirsty.penkman@york.ac.uk
Nature
|August 2, 2011
Resumen
La aminostratigrafía utilizando opercula de gasterópodos proporciona una línea de tiempo robusta para las secuencias del Cuaternario Británico. Este método vincula los registros terrestres con las etapas de isótopos marinos, revelando patrones de ocupación humana a lo largo de los ciclos glaciales e interglaciales.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Geología Cuaternaria Geología Cuaternaria
- La bioestratigrafía es una estratigrafía biológica.
Sus antecedentes:
- El período Cuaternario de la Tierra presenta glaciales y interglaciales cíclicos, lo que desafía la correlación de los registros terrestres.
- La aminostratigrafía ofrece un método potencial para alinear las secuencias terrestres con las etapas de isótopos marinos (MIS).
Objetivo del estudio:
- Desarrollar una aminostratigrafía completa para el Pleistoceno británico utilizando operculas de gasterópodos de agua dulce.
- Establecer un marco de datación robusto para las secuencias terrestres cuaternarias.
Principales métodos:
- Análisis de la degradación de aminoácidos (Asx, Glx, Ser, Ala, Val) en 470 operculas de 74 sitios británicos.
- Clasificación por edad relativa basada en el grado de degradación de las proteínas.
Principales resultados:
- Se estableció una nueva aminostratigrafía consistente con los datos estratigráficos existentes.
- Se han confirmado cuatro etapas interglaciales entre el Anglio (MIS 12) y el Holoceno.
- La ocupación humana en Gran Bretaña se identificó en las etapas interglaciales posteriores al MIS 15, con ausencia durante el MIS 5e.
- Confirmación de que el óptimo interestadial de Upton Warren es anterior al MIS 3.
Conclusiones:
- La nueva aminostratigrafía proporciona un marco confiable para la investigación cuaternaria.
- Apoya la reconstrucción detallada del clima pasado, la biostratigrafía y los eventos arqueológicos.
- Refine la comprensión de la presencia y ausencia humana durante los períodos clave del Cuaternario.
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