Microfósiles del grupo Guadalupe y la formación guaduas (campaniano-maastrichtlano) en la sección de Tausa, Cundinamarca, Colombia
- Autores: J. l. Martínez
- Localización: CT&F - Ciencia, tecnología y futuro, ISSN-e 0122-5383, Vol. 1, Nº. 1, 1995, págs. 65-81
- Idioma: inglés
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Resumen
A rich ossemblage of forominifers and ostracods recovered from the Guada lupe Gmup and the base of the Guoduo s Formofion in the Taus□ section are described ond i llustroted. The Guadalupe Group is choracterized by o low microfounal diversity dominated by the buliminids Siphogenerinoides ewaldi and Siphogenerinoides bramlettei. lncrements in microfouno l diversity oppeor to correspond fo the midd le port of Tronsgressive System Trods. Siphogenerínoides bromlettei (lote Maostrichtion in oge) supersedes Síphogenerinoides ewaldi (lote Componion in oge); the occurrence of the lwo taxo corresponds to the first sequence boundory in the Ploeners Formo/ion of the Guadalupe G roup. The first occurrence of S. bromleHei appear s to be "isochronous" in northern South Americo. The base of the Guaduos Formol"ion is chorocterized by o high diversity· of colcoreous benthonic foraminifero (rotaliids). Microfossils from the Guadalupe Group and Guaduos Formotion were offected by two taphonomic processes:(l ) koolinite infilling previous to dissolulion of tests during the mesodiogenetic stage, and (2) pyrite infill ing and pyritization (in sulfidic microenvironments) previous to dissolution of tests during the eodiogenefic sioge.
