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Datos de carbono-14 en gran pila: correlación de las cronologías de tierra y mar
Science (New York, N.Y.)
|January 8, 1982
Resumen
La datación por radiocarbono revela cambios climáticos durante 140.000 años en Francia. El período frío Weichselian Medio comenzó hace 70.000 años, marcado por la pérdida de bosques de hoja caduca.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Geología del Cuaternario geología cuaternaria.
- Palinología Palinología.
Sus antecedentes:
- Los registros de polen continental ofrecen información sobre las dinámicas climáticas pasadas.
- Grande Pile en el noreste de Francia conserva una secuencia continua de polen.
- Comprender la variabilidad climática a largo plazo es crucial para predecir los cambios futuros.
Objetivo del estudio:
- Para establecer una cronología precisa para el registro de polen de Grande Pile.
- Para reconstruir los cambios climáticos en los últimos 140.000 años.
- Para correlacionar los eventos climáticos continentales con los registros de isótopos oceánicos.
Principales métodos:
- Se obtuvieron dieciséis fechas de radiocarbono para establecer un marco cronológico.
- Análisis del registro continuo de polen continental de Grande Pile.
- Comparación con los registros establecidos de la etapa de isótopos de oxígeno oceánico.
Principales resultados:
- Se estableció una cronología detallada que se remonta a 70.000 años para el registro de la Grande Pile.
- El inicio del período frío de Weichselian Medio está fechado a 70.000 años antes del presente (B.P. En el caso de las personas con discapacidad, se considerará que:
- Este evento climático se corresponde con la desaparición de los bosques de hoja caduca en el sitio.
Conclusiones:
- El Weichselian Temprano ahora se coloca antes de 70.000 años B.P.
- Se demuestra una fuerte correlación entre el clima continental (Grande Pile) y los registros oceánicos (isótopos de oxígeno) hasta 70.000 años BP.
- Una mayor correlación más allá de los 70.000 años BP. se propone. se propone.
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