Estudio bioestratigráfico y paleoambiental de la Formación Río Turbio (Eoceno Medio a Superior) en el sudoeste de Patagonia (Argentina) basado en quistes de dinoflagelados

• Main Authors: González Estebenet, María S., Guerstein, Gladys R., Casadio, SIlvio Alberto
• Language: Spanish
• Published: 2015
• Subjects: Meteorología y Ciencias Atmosféricas; Dinofl Agellate Cysts; Middle-late Eocene; Drake Passage; Biostratigraphy; Paleoenvironment; Argentina; Austral; Patagonia; Antarc*; Antarctica
• Online Access: https://rid.unrn.edu.ar/jspui/handle/20.500.12049/2606; https://hdl.handle.net/20.500.12049/2606; http://www.sbpbrasil.org/pt/revista-edicoes-anteriores?id_revista=43; https://doi.org/10.4072/rbp.2015.3.08; http://hdl.handle.net/11336/57617

Fil: González Estebenet, María S. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina Fil: González Estebenet, María S. Universidad Nacional del Sur. Departamento de Geología; Argentina Fil: González Estebenet, María S. Instituto Geológico del Sur; Argentina Fil: Guerstein, Gladys R. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina Fil: Guerstein, Gladys R. Universidad Nacional del Sur. Departamento de Geología; Argentina Fil: Guerstein, Gladys R. Instituto Geológico del Sur; Argentina Fil: Casadio, Silvio A. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Fil: Casadio, Silvio A. Universidad Nacional de Río Negro; Argentina During the middle and late Eocene the Austral Basin, in southern Patagonia (Argentina), was fl ooded by an AtlanticOcean transgression, which was responsible for the deposition of the upper member of the Río Turbio Formation. We haveanalyzed the dinofl agellate cyst assemblages from this stratigraphic section in order to provide a biostratigraphic frameworkand reconstruct the paleogeographic and paleoceanographic conditions in this area. Dinofl agellate cyst events recorded werecompared and interpreted based taking into account other records recognized for the South Pacifi c Ocean. The comparisonallowed us to suggest an age between 45.5 Ma (mid-Lutetian) and 33.5 Ma (Priabonian) for the upper member of the RioTurbio Formation. We recognized three zones of dinofl agellate cysts. Zone I presents an alternating dominance betweenEnneadocysta dictyostila, Defl andrea antarctica and Vozzhennikovia apertura indicating two sea level rises. Zone II isdominated by V. apertura suggesting high trophic levels and cool waters in a shallow-marine coastal environment. The lowerpart of the Zone III shows a high abundance of Turbiosphaera fi losa with different ...