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El conjunto de isótopos de oxígeno revela la historia del agua de mar, la temperatura y el ciclo del carbono de la
1Te Aka Mātuatua, University of Waikato (Tauranga), Bay of Plenty, Tauranga, New Zealand.
Science (New York, N.Y.)
|February 8, 2024
Resumen
La Tierra
Área de la Ciencia:
- Geoquímica y paleoclimatología: Investigación de la habitabilidad a largo plazo de la Tierra y la dinámica climática.
Sus antecedentes:
- La habitabilidad persistente de la Tierra desde el Arqueo no se entiende bien.
- Las interpretaciones anteriores sugieren una Tierra temprana caliente, en contraste con los nuevos hallazgos.
Objetivo del estudio:
- Para reconstruir la historia de miles de millones de años de los isótopos de oxígeno del agua de mar (δ18O), la temperatura y la abundancia de arcilla.
- Investigar los factores que controlan la estabilidad climática y la habitabilidad a largo plazo de la Tierra.
Principales métodos:
- Utilizó un enfoque de conjunto de isótopos de oxígeno utilizando registros de esquisto, óxido de hierro, carbonato, sílice y fosfato.
- Análisis de los sedimentos del precámbrico para el contenido autogénico de arcilla y su relación con los cambios climáticos.
Principales resultados:
- Reveló un aumento en el agua de mar δ18O y un clima Proterozoico templado, desafiando la hipótesis de la "Tierra temprana caliente".
- Se han identificado cambios significativos en la abundancia de arcilla marina y terrestre relacionados con las principales transiciones climáticas.
- Se demostró que los cambios en la formación de arcilla influyeron en el enriquecimiento de agua de mar con 18O y en la estabilidad climática.
Conclusiones:
- El sistema climático de la Tierra ha sido fuertemente amortiguado, con un clima Proterozoico templado.
- El cambio climático inverso, impulsado por cambios en la formación de arcilla, jugó un papel crucial en el mantenimiento de la estabilidad climática y las primeras condiciones de la Tierra.
- Los cambios en la abundancia de arcilla están relacionados con eventos de enfriamiento, la evolución de la vida silícica y la radiación de las plantas.
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