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La última transición glaciar-Holoceno en el sur de Chile
K D Bennett1, S G Haberle, S H Lumley
1Quaternary Geology, Department of Earth Sciences, Uppsala University, Villavägen 16, S-752 36 Uppsala, Sweden. Keith.Bennett@geo.uu.se
Science (New York, N.Y.)
|October 13, 2000
Resumen
El evento de enfriamiento del Younger Dryas en el Atlántico Norte no fue un fenómeno global. Nuevas evidencias del sur de Chile indican que este enfriamiento fue regional, afectando solo a la región del Atlántico Norte.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Ciencia Cuaternaria La ciencia cuaternaria es la ciencia cuaternaria.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- La última terminación glacial vio un calentamiento significativo en el Atlántico Norte.
- Este calentamiento fue interrumpido por la cronozona del Younger Dryas (YDC), un período de renovada actividad glacial.
- La naturaleza global o regional del enfriamiento de YDC sigue siendo una pregunta clave en paleoclimatología.
Objetivo del estudio:
- Investigar si el evento de enfriamiento del Younger Dryas fue un fenómeno global o restringido a la región del Atlántico Norte.
- Para reconstruir el paleoclima del hemisferio sur durante el YDC.
Principales métodos:
- Análisis de los registros cronológicos, sedimentológicos y paleoecológicos.
- Análisis de núcleos de sedimentos de pequeños lagos en el océano del sur de Chile.
Principales resultados:
- Los registros de sedimentos del sur de Chile no muestran evidencia de enfriamiento durante la cronozona de Younger Dryas.
- Esto indica una falta de enfriamiento significativo en las aguas superficiales del sur del Pacífico.
Conclusiones:
- El evento de enfriamiento del Younger Dryas fue probablemente un fenómeno regional, afectando principalmente al Atlántico Norte.
- Los hallazgos desafían las explicaciones globales para el YDC y apoyan un mecanismo centrado en el Atlántico Norte.
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