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Última paleointensidad geomagnética del pleistoceno y el holoceno en Hawai
Science (New York, N.Y.)
|October 15, 1993
Resumen
La paleointensidad geomagnética en Hawai muestra una reducción del 35% durante el último período glacial. Este hallazgo se alinea con el aumento de las tasas de producción de nucleidos cosmogénicos.
Área de la Ciencia:
- La geofísica es la geofísica.
- El paleomagnetismo es el paleomagnetismo.
- Ciencias de la Tierra Ciencias de la Tierra Ciencias de la Tierra
Sus antecedentes:
- La comprensión de la intensidad del campo geomagnético pasado (paleointensidad) es crucial para los estudios del campo magnético de la Tierra.
- Los datos de paleointensidad del Holoceno y del período glacial tardío proporcionan información sobre el comportamiento de campo a largo plazo.
Objetivo del estudio:
- Para estimar las grandes tendencias en la paleointensidad geomagnética durante la época del Holoceno.
- Para investigar las variaciones de intensidad geomagnética cerca del final del último período glacial.
- Para comparar los datos de paleointensidad hawaiana con los registros mundiales.
Principales métodos:
- Determinaciones de paleointensidad geomagnética utilizando flujos de lava con fecha de radiocarbono de la isla de Hawai.
- Comparación de datos hawaianos con conjuntos de datos paleomagnéticos de todo el mundo.
Principales resultados:
- Los flujos de lava hawaianos proporcionan estimaciones de las tendencias de paleointensidad geomagnética del Holoceno.
- La intensidad del campo geomagnético fue aproximadamente un 35% menor que el promedio del Holoceno entre hace 45.000 y 10.000 años.
- Esta reducción a largo plazo es consistente con el aumento de las tasas de producción de nucleidos cosmogénicos.
Conclusiones:
- Los datos de paleointensidad geomagnética de Hawai ofrecen información valiosa sobre las variaciones pasadas de la intensidad del campo.
- Una reducción significativa en la intensidad del campo geomagnético se produjo durante el Pleistoceno tardío (último período glacial).
- La disminución de paleointensidad observada apoya los modelos que vinculan la intensidad del campo geomagnético a la producción de nucleidos cosmogénicos.
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