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Estimación de la duración e intensidad de las glaciaciones de bolas de nieve del Neoproterozoico a partir de
Bernd Bodiselitsch1, Christian Koeberl, Sharad Master
1Department of Geological Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
Science (New York, N.Y.)
|April 12, 2005
Resumen
La evidencia de material extraterrestre, específicamente anomalías de iridio, encontradas en la base de los carbonatos de la capa apoya la teoría de las glaciaciones globales del Neoproterozoico y su rápido derretimiento. Esto indica un período glacial marino prolongado.
Área de la Ciencia:
- Geología Geología Geología.
- Paleoclimatología Paleoclimatología
- Astrogeología y Astrogeología.
Sus antecedentes:
- La Era Neoproterozoica concluyó con un entorno de súper invernadero, desencadenando el rápido derretimiento del hielo y la formación de carbonato en la capa.
- La glaciación global concentraría material extraterrestre en el hielo, que se precipitaría durante los eventos de fusión.
Objetivo del estudio:
- Para investigar la presencia de material extraterrestre en el límite de las glaciaciones del Neoproterozoico y los carbonatos de la capa.
- Confirmar la extensión de las glaciaciones globales del Neoproterozoico y refinar la duración del episodio glacial marino.
Principales métodos:
- Análisis de tres núcleos de perforación del cratón del Congo Oriental.
- Identificación de anomalías de iridio (Ir) dentro de las capas de capas de carbonato.
Principales resultados:
- Se detectaron anomalías significativas de iridio en la base de los carbonatos de la tapa en todos los núcleos de perforación analizados.
- Estos hallazgos corroboran la ocurrencia de extensas glaciaciones globales del Neoproterozoico.
- Los datos sugieren que el episodio glacial marino duró un mínimo de 3 millones de años, y potencialmente hasta 12 millones de años.
Conclusiones:
- La presencia de anomalías de iridio proporciona una fuerte evidencia de deposición de material extraterrestre durante las glaciaciones del Neoproterozoico.
- El estudio confirma la naturaleza global y la duración significativa de la cubierta de hielo del Neoproterozoico, en particular la glaciación de Marino.
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