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La disolución y sedimentación de carbonatos en el margen continental del Atlántico medio
Science (New York, N.Y.)
|September 3, 1982
Resumen
El contenido de carbonato de calcio de los sedimentos en el margen continental del Atlántico medio aumenta con la profundidad, con una notable zona baja en carbonato vinculada a una disolución intensa. La preservación mejora por debajo de los 4400 metros donde se encuentra la Corriente Subterránea de la Frontera Occidental.
Área de la Ciencia:
- Geología marina Geología marina.
- La geoquímica es la geoquímica.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- La composición de los sedimentos varía a través de los márgenes continentales.
- Las corrientes oceanográficas influyen en la diagenesis y preservación de los sedimentos.
- El contenido de carbonato de calcio es un indicador clave de las condiciones de los sedimentos marinos.
Objetivo del estudio:
- Para determinar el contenido de carbonato de calcio en la parte superior del núcleo a lo largo de dos transectos.
- Para investigar la relación entre el contenido de carbonato, la profundidad y la disolución.
- Para entender la influencia de la Corriente Subterránea de la Frontera Occidental en la preservación de los carbonatos.
Principales métodos:
- Análisis de muestras de núcleo superior del margen continental del Atlántico medio.
- Determinación del contenido de carbonato de calcio (en peso).
- Examen de los índices de disolución de los sedimentos.
Principales resultados:
- El contenido de carbonato aumenta de ~5% en la pendiente superior a >30% en la subida superior.
- Una zona baja en carbonato (3000-4400 metros) muestra evidencia de una disolución intensa.
- Por debajo de los 4400 metros, la preservación del carbonato mejora, correlacionándose con la Corriente Subterránea de la Frontera Occidental.
Conclusiones:
- La Corriente Subterránea de la Frontera Occidental tiene un impacto significativo en la disolución y preservación del carbonato.
- La profundidad y la proximidad a la Corriente Subterránea de la Frontera Occidental son factores críticos que controlan la geoquímica de los sedimentos.
- Comprender estos procesos es vital para las reconstrucciones paleoceanográficas.
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