Barremian planktonic foraminiferal events correlated with the ammonite zones from the San Lucas Formation, Michoacán (SW Mexico).
We studied the Tiringueo section from the San Lucas Formation, located in the state of Michoacán,SW Mexico. The section is a flysch sequence consisting of a rhythmic deposit of shale, siltstone, and fineto medium graded sandstone interbedded with limestone. The sequence contains ammonites, foraminif...
| Autores: | , , |
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| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2005 |
| País: | México |
| Recursos: | Universidad Nacional Autónoma de México |
| Repositorio: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:57222108 |
| Acesso em linha: | https://www.redalyc.org/articulo.oa?id=57222108 |
| Access Level: | acceso abierto |
| Palavra-chave: | Ciencias de la Tierra Mexico Barremian Michoacán San Lucas Formation planktonic foraminifera |
| Resumo: | We studied the Tiringueo section from the San Lucas Formation, located in the state of Michoacán,SW Mexico. The section is a flysch sequence consisting of a rhythmic deposit of shale, siltstone, and fineto medium graded sandstone interbedded with limestone. The sequence contains ammonites, foraminiferaand radiolarians.The biostratigraphic analysis, based on the planktonic foraminifera and ammonites, permitted therecognition of the biostratigraphic units established on both fossil groups, for first time in SW Mexico.Although the planktonic foraminifera are scarce and poorly preserved, some important events such as thefirst occurrence of Hedbergella similis, Globigerinelloides blowi and Globigerinelloides aptiensis werecorrelated with the ammonite zones. By means of these foraminiferal events, the Zones of Hedbergellasimilis and Globigerinelloides blowi partim (early and late Barremian) were identified. The faunalassemblage and distinctive lithological characteristics suggest that the San Lucas Barremian sequencewas deposited in pelagic conditions. |
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