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Extinciones terminales del Cretácico en el área de Hell Creek, Montana: compatibles con una extinción catastrófica
Resumen
Los errores estratigráficos en Montana crearon una falsa idea de las faunas de transición en el límite Cretácico-Terciario. La reevaluación de estas faunas en los canales del Paleoceno apoya un evento de extinción catastrófica, alineando los registros terrestres y marinos.
Área de la Ciencia:
- Paleontología Paleontología.
- La estratigrafía es la estratigrafía.
- Geología Geología Geología.
Sus antecedentes:
- Las correlaciones estratigráficas inexactas en el área de Hell Creek, Montana, han llevado a la suposición de faunas de vertebrados de transición (Bug Creek Anthills) en el último Cretácico.
- Esta suposición desafía el concepto de una rotación catastrófica en el límite Cretácico-Terciario.
Objetivo del estudio:
- Para reevaluar la posición estratigráfica de las faunas de transición en el área de Hell Creek.
- Para determinar si estas faunas apoyan o refutan un evento de extinción catastrófica en el límite Cretácico-Terciario.
Principales métodos:
- Análisis estratigráfico detallado en el área de Hell Creek, Montana.
- Reexamen de los entornos de deposición de la fauna de las antillas de Bug Creek.
Principales resultados:
- Las faunas de transición se establecieron en los canales del Paleoceno que atraviesan la frontera entre el Cretácico y el Terciario.
- Esta reevaluación resuelve las discrepancias entre los registros de la fauna terrestre y marina.
Conclusiones:
- El registro de la fauna terrestre es compatible con el registro marino.
- Los hallazgos apoyan un evento de extinción catastrófica en el límite Cretácico-Terciario, refutando la existencia de faunas de transición en el último Cretácico.
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