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La periodicidad en la tasa de enterramiento de fósforo marino
1Theoretical Geophysics Group, National Geophysical Research Institute, Hyderabad, India. postmast@csngri.ren.nic.in
Nature
|September 7, 2001
Resumen
Los registros evolutivos geomarinos revelan un ciclo significativo de 33 millones de años. Este estudio analizó las tasas de sepultura de fósforo sedimentario marino, apoyando patrones cíclicos en la Tierra.
Área de la Ciencia:
- Ciencias de la Tierra, Paleoclimatología, Oceanografía
Sus antecedentes:
- Existe un debate con respecto a una periodicidad de 26-33 millones de años en los registros de la Tierra.
- Los registros evolutivos geomarinos son cruciales para identificar tales ciclos.
Objetivo del estudio:
- Para investigar la posible periodicidad de 26 a 33 millones de años en la historia de la Tierra.
- Para analizar la tasa de sepultura de fósforo sedimentario marino (PBR) como un indicador de los ciclos del sistema terrestre.
Principales métodos:
- Análisis de la tasa de sepultura de fósforo sedimentario marino (PBR).
- Análisis estadístico para identificar componentes armónicos frente al ruido de fondo.
Principales resultados:
- Se detectó un componente armónico estadísticamente significativo de 33 +/- 3 millones de años.
- Las fluctuaciones de la tasa de entierro de fósforo indican el acoplamiento del clima, la intemperie y la productividad.
Conclusiones:
- Los hallazgos apoyan la existencia de patrones cíclicos en los procesos geomarinos.
- El ciclo de 33 Myr proporciona evidencia de cambios periódicos a largo plazo en los sistemas terrestres.
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