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Clarkforkian edad de los mamíferos terrestres: definición revisada, zonificación y correlaciones intercontinentales

Science (New York, N.Y.)

|May 16, 1980

Resumen

Nuevas evidencias confirman la Edad de los Mamíferos Terrestres de Clarkforkian en América del Norte, definida por la llegada de nuevas especies. Esta edad se divide en tres zonas y se correlaciona con la fauna del Paleoceno-Eoceno a nivel mundial.

Área de la Ciencia:

Paleontología Paleontología.
La estratigrafía es la estratigrafía.
Evolución de los mamíferos Evolución de los mamíferos

Sus antecedentes:

La Edad de los Mamíferos Terrestres de Clarkforkian es una unidad cronoestratigráfica crucial en la paleontología de mamíferos de América del Norte.
La definición de las fronteras y subdivisiones precisas de esta edad es esencial para las correlaciones intercontinentales.

Objetivo del estudio:

Presentar nuevas evidencias faunísticas y estratigráficas que apoyen la validez de la Edad de los Mamíferos Terrestres de Clarkforkian.
Para definir los límites temporales del Clarkforkian basado en la primera aparición de taxones inmigrantes.
Para subdividir el Clarkforkian en su área tipo y establecer correlaciones regionales.

Principales métodos:

Análisis de nuevas faunas de mamíferos fósiles.
Examen estratigráfico de secuencias sedimentarias en el noroeste de Wyoming.
Correlación biostratigráfica utilizando taxones inmigrantes y conjuntos faunísticos.

Principales resultados:

Una nueva evidencia valida la edad de los mamíferos terrestres de Clarkforkian.
El Clarkforkian se subdivide en tres zonas distintas en su área tipo.
La aparición inicial de taxones inmigrantes define los límites del Clarkforkian.
Las faunas de Clarkforkian muestran una correlación aproximada con las últimas faunas del Paleoceno-Eoceno más temprano en Europa y Mongolia.

Conclusiones:

La edad de los mamíferos terrestres de Clarkforkian es una unidad cronostratigráfica bien definida y válida.
Las definiciones propuestas de zonificación y límites facilitan una mejor correlación de los registros continentales de América del Norte.
Este estudio mejora la comprensión de la rotación de la fauna de mamíferos y las conexiones paleogeográficas durante la transición Paleoceno-Eoceno.

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