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Pruebas de isótopos triples de oxígeno para una productividad primaria limitada a mediados del Proterozoico
Peter W Crockford1,2,3, Justin A Hayles4,5, Huiming Bao5,6
1McGill University, Montreal, Quebec, Canada. peter.crockford@mail.mcgill.ca.
Nature
|July 20, 2018
Resumen
La evidencia de sulfatos de hace 1.400 millones de años revela una biosfera global menos productiva durante el eón Proterozoico. Las mediciones de isótopos triples de oxígeno (delta 17O) indican una atmósfera antigua distinta, que afecta nuestra comprensión de la Tierra temprana
Área de la Ciencia:
- Geoquímica
- Paleoclimatología
- Biogeociencia
Sus antecedentes:
- Se debate la productividad de la antigua biosfera de la Tierra, con una suposición común de menor productividad antes de los ecosistemas eucariotas complejos.
- La evidencia geológica directa que apoya esta afirmación ha sido escasa, lo que dificulta una comprensión clara de la dinámica temprana de la biosfera.
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