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Interacción del magnesio con la superficie de la calcita en el agua de mar
Science (New York, N.Y.)
|August 31, 1979
Resumen
La calcita de magnesio se forma sobre la calcita pura en el agua de mar natural, haciéndose menos soluble. Esta reducción de la solubilidad afecta a la acumulación de calcita en aguas profundas, lo que afecta a la composición de los sedimentos marinos.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Geología marina Geología marina.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- La calcita es un componente importante de los sedimentos marinos.
- La química del agua de mar influye en la precipitación y disolución de minerales.
- La comprensión de las transformaciones minerales es clave para la geoquímica marina.
Objetivo del estudio:
- Para investigar la formación y las propiedades de los crecimientos de calcita en el agua de mar natural.
- Para cuantificar el cambio en la solubilidad de la calcita debido a la incorporación de magnesio.
- Evaluar las implicaciones de la formación de calcita de magnesio en la acumulación de sedimentos de aguas profundas.
Principales métodos:
- Exposición de muestras de calcita al agua de mar superficial natural.
- Análisis químico de la composición del crecimiento excesivo (contenido de magnesio).
- Mediciones de solubilidad de calcita pura versus calcita magnesiana en agua de mar.
Principales resultados:
- Crecimiento excesivo de calcita de magnesio (4 ± 2 mol% MgCO3) formado en la calcita.
- La calcita de magnesio exhibió aproximadamente un 30% menos de solubilidad que la calcita pura en agua de mar.
- Esta reducción de la solubilidad indica un cambio significativo en el comportamiento geoquímico de la calcita.
Conclusiones:
- La calcita de magnesio se forma fácilmente en la calcita en contacto con el agua de mar superficial.
- La disminución de la solubilidad de la calcita de magnesio tiene implicaciones sustanciales para la preservación de la calcita en entornos marinos.
- Este proceso puede influir significativamente en la tasa de acumulación de calcita en los sedimentos de aguas profundas.
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