INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
Non-marine Cretaceous palynomorph biostratigraphy of Argentina. A brief summary.
PRAMPARO, MERCEDES B
Journal of Stratigraphy
Science Press (Chinese Academy of Sciences)
Lugar: Nanjing; Año: 2012 vol. 36 p. 212 - 212
Abstract An evaluation of the Cretaceous palynostratigraphy has been undertaken, by reviewing published data of the geological units with palynomorphs. Formal and informal biozonation schemes were compiled from seven Cretaceous Argentinean basins presented from north to south: the Salta Group Basin, San Luis Basin, Neuquen Basin, Austral Basin, Deseado Massif, San Jorge Gulf Basin, extra-andean Patagonia. The Early Cretaceous palynological associations are relatively well-known in Argentina; however there is sparse published literature describing and discussing Late Cretaceous miofloras. The association of coniferous gymnosperm pollen grains, with conifer affinity: Cyclusphaera-Balmeiopsis-Classopollis dominates in all the palynofloras from the Valaginian to the Aptian. Celyphus rallus (filamentous cyanobacteria) appears together with Cyclusphaera but disappears in the Barremian in all the Patagonian basins. Pollen grains belonging to basal angiosperms are important stratigraphic markers in Aptian sediments and younger, and have been used to define palynozones. Peninsulapollis gillii which corresponds to the first record of the Proteaceae family in Argentina is one of the few species, which occurs in all the late Campanian- Maastrichtian associations, sometimes together with Grapnelispora loncochensis. Their presence could be indicative of a provisional palynozone. A preliminary correlation chart of the palynozones is presented together with a chart of the main Cretaceous stratigraphic units.