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Updated: Jul 11, 2026

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Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS
Published on: August 31, 2017
El comienzo de la oxidación del azufre en entornos continentales: hace aproximadamente 2,2 x 109 años
Resumen
La reducción disimilatoria de sulfato comenzó en ambientes marinos hace más de 2.800 millones de años. Sin embargo, las reacciones redox continentales de azufre no fueron significativas hasta hace 2.200 millones de años, según los datos del Supergrupo Huroniano.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Ambientes de la Tierra Temprana Los primeros ambientes de la Tierra Temprana.
- Los ciclos biogeoquímicos son ciclos biogeoquímicos.
Sus antecedentes:
- La reducción disimilatoria del sulfato (DSR) es un proceso microbiano clave que influye en el ciclo del azufre.
- Estudios anteriores sugirieron que la DSR comenzó en entornos marinos antes de hace 2.800 millones de años, basándose en datos de isótopos de azufre.
Objetivo del estudio:
- Investigar el momento y la importancia de las reacciones redox de azufre en entornos continentales durante la historia temprana de la Tierra.
Principales métodos:
- Análisis de la abundancia de isótopos de azufre en formaciones rocosas.
- Examen geológico del supergrupo hurónico en Canadá.
Principales resultados:
- La evidencia sugiere que las reacciones oxidativo-reductivas significativas que involucran azufre en entornos continentales no ocurrieron antes de hace aproximadamente 2.200 millones de años.
- Esto contrasta con el inicio anterior de la DSR en entornos marinos.
Conclusiones:
- El ciclo redox de azufre continental se rezagó con respecto al DSR marino.
- El ciclo biogeoquímico de azufre de la Tierra primitiva fue espacialmente heterogéneo, con distintos regímenes marinos y terrestres.
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