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Cronología de las glaciaciones hawaianas
Science (New York, N.Y.)
|January 7, 1977
Resumen
El Mauna Kea se encuentra en Mauna Kea.
Área de la Ciencia:
- Geología Geología Geología.
- Paleoclimatología Paleoclimatología
- Ciencia Cuaternaria La ciencia cuaternaria es la ciencia cuaternaria.
Sus antecedentes:
- Mauna Kea, Hawai, conserva un valioso registro de la actividad glacial pasada.
- Comprender la historia glacial es crucial para reconstruir las dinámicas climáticas pasadas.
Objetivo del estudio:
- Para determinar el momento y la extensión de la glaciación pasada en Mauna Kea.
- Para correlacionar los eventos glaciales hawaianos con los patrones climáticos globales.
Principales métodos:
- Datamiento radiométrico de materiales volcánicos (potasio/argon y carbono-14).
- Análisis de los flujos de lava y las capas de tefra interestratificadas con depósitos glaciales.
Principales resultados:
- Cuatro episodios distintos de glaciación de la capa de hielo en el Mauna Kea.
- Las edades de culminación de estas glaciaciones: hace aproximadamente 20,000, 55,000, 135,000 y 250,000 años.
- Correlación de estos eventos glaciales con las etapas de isótopos marinos 2, 4, 6 y 8.
Conclusiones:
- La historia glacial del Mauna Kea proporciona un registro terrestre de las edades de hielo pasadas.
- Los episodios glaciales identificados corresponden a períodos de alto volumen de hielo global, lo que apoya las reconstrucciones de modelos climáticos.
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