Carlos O. Limarino, Laura Jazmín Schencman, Pablo Joaquín Alonso Muruaga, Silvia Nelida Césari
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Revista de la Asociación Geológica Argentina Vol 74, No 4 (2017)
En este trabajo se discuten la nomenclatura estratigráfica, evolución paleoambiental, contenido fósil y edad de las unidades carboníferas y pérmicas de la Precordillera septentrional. El intervalo Mississippiano es caracterizado desde el punto de vista litológico en el área tipo del Grupo Angualasto (Sierra de Malimán), examinando las relaciones con secuencias de similar edad expuestas en otros sectores de la Precordillera (formaciones Jagüel, Agua de Lucho, Cerro Tres Cóndores y Loma de Los Piojos). La evolución paleoambiental de este intervalo incluye varios episodios transgresivos y al menos un evento glacial durante el Viseano-Serpukhoviano temprano. Para el Pennsylvaniano inferior y medio se discute el significado estratigráfico de las formaciones Guandacol y Tupe (Grupo Paganzo), estableciéndose las relaciones con las formaciones Río del Peñón, Quebrada Larga, Panacán y Volcán definidas por autores previos. Todas estas unidades representan la sedimentación postorogénica acaecida luego del levantamiento de la Protoprecordillera ocurrido entre el Devónico tardío y el Mississippiano. Desde el punto de vista paleoambiental este intervalo representa condiciones glaciarias (base de la Formación Guandacol), un evento transgresivo postglacial y la posterior progradación de sistemas fluviodeltaicos (parte media y superior de la Formación Guandacol). Durante la depositación de la Formación Tupe la sedimentación fue dominantemente fluvial e interrumpida por al menos dos eventos transgresivos. Finalmente el Carbonífero más tardío y Pérmico temprano (Gzheliano-Cisuraliano) aparece representado en la Precordillera septentrional por la secuencia de bancos rojos perteneciente a la Formación Patquía, esta unidad resulta temporalmente correlacionable con los miembros medio y superior de la Formación Quebrada Larga o Río del Peñón.
Stratigraphic analysis of the Neopaleozoic sequences in the northern Precordillera.
This paper deals with the stratigraphic nomenclature, paleoenvironmental evolution, fossil assemblages and age of the Carboniferous and Permian units outcropping in the northern Precordillera. The Mississippian stratigraphy is characterized in the type area of the Angualasto Group (sierra de Malimán) and the relations with other sequences of similar age exposed in the Precordillera examined in detail (Jagüel, Agua de Lucho, Cerro Tres Cóndores and Loma de Los Piojos Formations). The paleoenvironmental evolution of the Mississippian comprises several transgresive events and at least one glacial episode during the Visean-early Serpukhovian. Regarding the lower and middle Pennsylvanian, the stratigraphic meaning of the Guandacol and Tupe Formations (Paganzo Group) is analyzed, as well as the correlations with the Río del Peñón, Quebrada Larga, Panacán and Volcán Formations which were defined by previous authors in Precordillera. All these units represent the post orogenic sedimentation that took place after the uplift of the Protoprecordillera during the Late Devonian - Mississippian. From the paleoenvironmental point of view, the Lower and Middle Pennsylvanian interval was dominated by glacial conditions (base of the Guandacol Formation), followed by a transgressive postglacial event and the later progradation of fluviodeltaic systems (middle and upper part of the Guandacol Formation). During the deposition of the Tupe Formation, the sedimentation was dominantly fluvial and interrupted by two transgressive episodes. Finally, the red beds of the Patquía Formation records the latest Carboniferous and early Permian (Gzhelian-Cisuralian), this unit is a time equivalent with the middle and upper members of the Quebrada Larga and Río del Peñón Formations.
This paper deals with the stratigraphic nomenclature, paleoenvironmental evolution, fossil assemblages and age of the Carboniferous and Permian units outcropping in the northern Precordillera. The Mississippian stratigraphy is characterized in the type area of the Angualasto Group (sierra de Malimán) and the relations with other sequences of similar age exposed in the Precordillera examined in detail (Jagüel, Agua de Lucho, Cerro Tres Cóndores and Loma de Los Piojos Formations). The paleoenvironmental evolution of the Mississippian comprises several transgresive events and at least one glacial episode during the Visean-early Serpukhovian. Regarding the lower and middle Pennsylvanian, the stratigraphic meaning of the Guandacol and Tupe Formations (Paganzo Group) is analyzed, as well as the correlations with the Río del Peñón, Quebrada Larga, Panacán and Volcán Formations which were defined by previous authors in Precordillera. All these units represent the post orogenic sedimentation that took place after the uplift of the Protoprecordillera during the Late Devonian - Mississippian. From the paleoenvironmental point of view, the Lower and Middle Pennsylvanian interval was dominated by glacial conditions (base of the Guandacol Formation), followed by a transgressive postglacial event and the later progradation of fluviodeltaic systems (middle and upper part of the Guandacol Formation). During the deposition of the Tupe Formation, the sedimentation was dominantly fluvial and interrupted by two transgressive episodes. Finally, the red beds of the Patquía Formation records the latest Carboniferous and early Permian (Gzhelian-Cisuralian), this unit is a time equivalent with the middle and upper members of the Quebrada Larga and Río del Peñón Formations.
http://ppct.caicyt.gov.ar/index.php/raga/article/view/9618
