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Microfósiles del Proterozoico temprano y cementación de cuarzo penecontemporaneo en la formación de hierro Sokoman,
Science (New York, N.Y.)
|January 30, 1981
Resumen
Los microfósiles del Proterozoico temprano de las formaciones Sokoman y Gunflint son morfológicamente similares. Las diferencias en las comunidades de vida temprana son ecológicas, no evolutivas, con microfósiles encontrados en peloides dentro de formaciones de hierro.
Área de la Ciencia:
- Paleontología Paleontología.
- Geología Geología Geología.
- Astrobiología Astrobiología.
Sus antecedentes:
- Las primeras formaciones de hierro del Proterozoico albergan importantes fósiles microbianos.
- La vida microbiana en los entornos de la Tierra antigua proporciona información sobre la evolución temprana y la habitabilidad.
Objetivo del estudio:
- Para comparar los conjuntos de microfósiles del Proterozoico temprano de la Formación de Hierro Sokoman con los de la Formación Gunflint.
- Para determinar si las diferencias observadas en las primeras comunidades microbianas son ecológicas o temporales.
- Para investigar la relación entre la preservación de microfósiles y la cementación de sílice en formaciones de hierro arenoso.
Principales métodos:
- Análisis morfológico de microfósiles de la Formación de Hierro de Sokoman.
- Comparación de los conjuntos de microfósiles de Sokoman con los datos publicados de la Formación Gunflint y el Supergrupo Belcher.
- Análisis petrográfico de las formaciones de hierro para comprender la distribución de microfósiles y la cementación de sílice.
Principales resultados:
- Los microfósiles de la Formación de Hierro Sokoman son indistinguibles de los microfósiles de la Formación Gunflint en su morfología y estructura comunitaria.
- El conjunto de Sokoman es contemporáneo de las cianobacterias similares a Bitter Springs del supergrupo Belcher.
- Los microfósiles en las formaciones de hierro arenoso están restringidos a los peloides, ausentes en el cemento de sílice.
- La evidencia sugiere una cementación de sílice penecontemporanea y una cementación temprana común en estas formaciones.
Conclusiones:
- Las diferencias entre las principales microbiotas del Proterozoico temprano son principalmente ecológicas, no evolutivas.
- La preservación de los microfósiles está relacionada con el entorno de deposición y la diagenesis, específicamente la cementación de sílice.
- Los primeros ecosistemas microbianos del Proterozoico exhibieron diversidad ecológica dentro de restricciones evolutivas similares.
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