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Updated: Apr 13, 2026

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No hubo glaciación bipolar extrema durante el cambio de compensación de calcita del Eoceno principal

Kirsty M Edgar¹, Paul A Wilson, Philip F Sexton

¹National Oceanography Centre, School of Ocean and Earth Science, European Way, Southampton, SO14 3ZH, UK.

|August 24, 2007

Resumen

Las grandes capas de hielo no estaban presentes en el hemisferio norte hace 41,6 millones de años. Los registros de sedimentos marinos indican que las capas de hielo de la Antártida fueron la principal fuente de glaciación durante este período.

Área de la Ciencia:

Paleoclimatología Paleoclimatología
Geología marina Geología marina.

Sus antecedentes:

El límite entre el Eoceno y el Oligoceno (aprox. 34 millones de años) marcó el establecimiento permanente de la capa de hielo antártica y la profundización de la profundidad de compensación de calcita oceánica (CCD).
Las opiniones anteriores sugirieron que la glaciación del hemisferio norte comenzó mucho más tarde (hace 11-5 millones de años).
Evidencias recientes, incluyendo el rafting de hielo del Eoceno y las estimaciones del volumen de hielo global, desafiaron esta línea de tiempo, sugiriendo una glaciación anterior en el hemisferio norte.

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