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Reciclaje sedimentario a largo plazo de anomalías de isótopos raros de azufre
Christopher T Reinhard1, Noah J Planavsky, Timothy W Lyons
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91126, USA.
Nature
|April 26, 2013
Resumen
Las anomalías de isótopos de azufre no dependientes de la masa (NMD), clave para la atmósfera de la Tierra temprana, persisten en las rocas debido al reciclaje de la corteza. Este "efecto de memoria de la corteza" significa que las señales pueden durar millones de años después de que aumenten los niveles de oxígeno atmosférico.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Paleoclimatología Paleoclimatología
- La geoquímica de los isótopos es la geoquímica de los isótopos.
Sus antecedentes:
- La acumulación de oxígeno atmosférico (O2) moldeó profundamente la química y la ecología de la superficie de la Tierra.
- Las anomalías de isótopos de azufre no dependientes de la masa (NMD) en las rocas son cruciales para reconstruir los primeros estados redox atmosféricos.
- La desaparición de las anomalías de NMD hace unos 2.32 mil millones de años marcó un cambio de niveles de oxígeno persistentemente bajos.
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