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Acidificación rápida del océano durante el máximo térmico del Paleoceno-Eoceno
James C Zachos1, Ursula Röhl, Stephen A Schellenberg
1Earth Sciences Department, Earth and Marine Sciences Building, University of California, Santa Cruz, Santa Cruz, CA 95064, USA. jzachos@emerald.uscs.edu
Science (New York, N.Y.)
|June 11, 2005
Resumen
El Máximo Térmico Paleoceno-Eoceno (PETM) causó una rápida disolución de carbonato en aguas profundas, lo que indica una liberación masiva de carbono. Este evento redujo drásticamente la profundidad de compensación de calcita (CCD) durante más de 100.000 años.
Área de la Ciencia:
- La paleoceanografía es la paleoceanografía.
- La geoquímica es la geoquímica.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- El Máximo Térmico Paleoceno-Eoceno (PETM) está vinculado a una liberación masiva de carbono, teorizada para bajar el pH del océano y acumular la profundidad de compensación de calcita (CCD).
- Comprender el impacto del PETM en la química oceánica y la disolución de carbonatos es crucial para reconstruir eventos climáticos pasados.
Objetivo del estudio:
- Investigar el momento y la extensión de la disolución de carbonato durante el PETM utilizando nuevos datos del núcleo de aguas profundas.
- Para refinar las estimaciones de la liberación de carbono y la respuesta oceanográfica durante este evento geológico significativo.
Principales métodos:
- Análisis de datos geoquímicos de cinco nuevas secciones de sedimentos de aguas profundas del Atlántico Sur.
- Examen de capas de sedimentos, incluida una capa de arcilla prominente, para inferir cambios en la profundidad del agua y la disolución de carbonato.
Principales resultados:
- Los datos geoquímicos revelan una rápida (<10.000 años) acumulación del CCD por más de 2 kilómetros durante el PETM.
- La evidencia sugiere que la disolución masiva de carbonato del fondo marino ocurrió coincidiendo con el PETM.
- El CCD mostró una recuperación gradual durante más de 100.000 años.
Conclusiones:
- El PETM se asoció con una liberación de carbono significativamente mayor de lo estimado anteriormente (> 2000 x 10 ^ 9 toneladas métricas).
- La rápida absorción oceánica de este carbono condujo a una disolución sustancial y duradera de los carbonatos.
- La retroalimentación del desgaste de silicatos jugó un papel en el secuestro permanente de este carbono liberado.
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