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Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
Origen del Mioceno tardío del sistema de subida de Benguela en el norte de Namibia
Resumen
El sistema de surgimiento de Benguela frente a Namibia probablemente comenzó a principios del Mioceno tardío, hace aproximadamente 10 millones de años. Esta iniciación trajo aguas frías y ricas en nutrientes, estableciendo el sistema moderno.
Área de la Ciencia:
- Geología marina Geología marina.
- La paleoceanografía es la paleoceanografía.
- Paleoclimatología Paleoclimatología
Sus antecedentes:
- El sistema ascendente de Benguela es un componente crucial del ecosistema marino del Océano Atlántico.
- Comprender su inicio proporciona información sobre las condiciones oceanográficas pasadas y la dinámica climática.
Objetivo del estudio:
- Para determinar el momento del inicio del sistema de surgencia de Benguela en el norte de Namibia.
- Para reconstruir las condiciones paleoceanográficas asociadas con el establecimiento del sistema.
Principales métodos:
- Análisis de los núcleos del Proyecto de Perforación en Aguas Profundas del sitio 362/362A.
- Examen de las tasas de acumulación de sedimentos.
- Estudio de la abundancia de diatomeas y las preferencias de temperatura de los microfósiles (foraminíferos plancticos, nanoplancton calcáreo, silicoflagelados).
- Evaluación de la productividad a través del contenido de carbono orgánico y la incorporación de fósforo en esqueletos calcáreos.
Principales resultados:
- Los datos sedimentológicos y paleontológicos indican el inicio de un importante y sostenido surgimiento en el Mioceno tardío temprano.
- El moderno sistema de surgencia de Benguela se remonta a aproximadamente 10 millones de años antes del presente.
- La evidencia apunta a la llegada de aguas frías y ricas en nutrientes a la superficie.
Conclusiones:
- El Mioceno tardío temprano marca el inicio del moderno sistema de surgimiento de Benguela.
- Este evento alteró significativamente el entorno marino frente al norte de Namibia.
- Los hallazgos contribuyen a comprender la evolución a largo plazo de los principales sistemas oceanográficos.
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