Latest Devonian to early Late Carboniferous biostratigraphy of northern Brazil: An update

Latest Devonian to early Late Carboniferous palynozones of northern Brazilian basins are revised and correlated with equivalent miospore biozones of western Europe. It is concluded that certain biozones in PETROBRAS' earlier regional scheme for the Lower Carboniferous are actually indistinguishable, because age implications and stratigraphic ranges of their zonal species are now known to differ markedly from those given in older Brazilian literature. A regional unconformity separates Late Visean strata from early Late Tournaisian or older sediments in the Amazon and western Solimoes Basins, as possibly also in the Parnaiba Basin. Marine faunal controls for Late Carboniferous carbonates, within sections of Amazonian basins which contain taeniate pollen, are partly discussed with reference to U.S. Midcontinent data, and demonstrated to exclude pre-Westphalian age assignments. On the other hand, a possible Late Namurian age is acceptable from the palynological Viewpoint for the oldest, dominantly terrigenous part of the Late Carboniferous sequence in the Solimoes Basin. This lacks taeniate bisaccates and seems to have no sedimentary equivalent in the neighbouring Amazon Basin. Results of the present study indicate that additional palynological investigations are needed in Early and late Carboniferous sections of the Parnaiba and Solimoes Basins.