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Pruebas geoquímicas de una euxinia extendida en el océano cámbrico posterior
Benjamin C Gill1, Timothy W Lyons, Seth A Young
1Department of Earth Sciences, University of California, 900 University Avenue, Riverside, California 92521, USA. bgill@fas.harvard.edu
Nature
|January 7, 2011
Resumen
La anoxia oceánica, o deficiencia de oxígeno, estaba muy extendida en el período cámbrico posterior, coincidiendo con la Excursión de Isótopos Positivos de Carbono de Steptoean (SPICE). Este evento tuvo un impacto significativo en la vida marina y la evolución durante este momento crítico.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- La paleoceanografía es la paleoceanografía.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La anoxia oceánica es un motor propuesto de extinciones masivas y una restricción de la radiación evolutiva.
- Las hipótesis sugieren que la deficiencia de oxígeno en los océanos subterráneos del Cámbrico posterior influyó en los eventos evolutivos.
- La evidencia física de la anoxia cámbrica generalizada ha sido escasa, lo que limita la exploración de sus vínculos evolutivos.
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