CONICET | Buscador de Institutos y Recursos Humanos

Palynostratigraphic and palynofacies analysis of the Springhill and Pampa Rincón Formations (Argentina) and Estratos con Favrella (Chile), studied from 30 core samples of nine wells located northeast Tierra del Fuego, are herein presented. The collected samples yielded an Upper Valanginian to Cenomanian(?) palynoflora from which 71 terrestrial species (spores and pollen) and 39 species of organic-walled phytoplankton are considered. A correlation was made with the Upper Valanginian-Lower Aptian Cyclusphaera psilata-Classopollis Zone (Neuquén Basin) and the Interulobites-Foraminisporis Assemblage Zone of the Austral Basin (Upper Valanginian-Upper Hauterivian) owing to the presence of bryophytic species such as Interulobites spp. and Polycingulatisporites spp. and the incoming of Cyclusphaera psilata Volkheimer and Sepúlveda. Celyphus rallus Batten and Balmeiopsis limbatus (Balme) Archangelsky are also common in this Zone. The Barremian tectifera-corrugatus Interval Zone (Austral Basin) was not recognized in the samples studied. The Antulsporites-Clavatipollenites Assemblage Zone of the Austral Basin (Aptian), which is characterized by early angiosperm pollen grains (Clavatipollenites hughesii Couper, Asteropollis asteroides Hedlund and Norris), and Cyclusphaera crassa Archangelsky among others is also recognized. Near the Aptian/Albian boundary, the succession of angiosperms is characterized by the appearance of rare tricolpates. A correlation with Australian basins based on dinoflagellate cysts is also given. Six types of palynofacies could be distinguished (palynofacies type 1-6), having in mind that variations in palynofacies types and the composition of palynomorph assemblages provide information about the depositional environments, deltaic, shallow marine, nearshore and offshore environments could be identified.

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