Unraveling the late Permian evolution of the Paraná Basin: a revised stratigraphic and sedimentological framework

Abstract Since its definition over 120 years ago, several key sedimentological and stratigraphic questions have emerged regarding the Estrada Nova succession (Serra Alta and Teresina/Corumbataí formations) of the Paraná Basin. These units developed during the disconnection of basin waters from Panthalassa and the progressive continentalization of southwestern Gondwana during the Permian, marking a distinctive stage in basin evolution. To clarify this interval, we integrated stratigraphic, sedimentological, paleontological, and geochronological data with detailed facies analysis across 28 measured sections in Mato Grosso, Goiás, São Paulo, and Paraná states. This regional survey refined stratigraphic correlation among late Permian units and revealed basin-scale filling patterns not previously recognized. Fischer diagram analysis allowed construction of accommodation curves showing striking similarities across successions in the northwestern, central, and southern basin. The recognition of a consistent stratigraphic architecture suggests depositional responses to climatic fluctuations, subsidence, and base-level changes were more homogeneous and synchronous than assumed. From a lithostratigraphic perspective, our revised framework simplifies debated stratigraphy by reaffirming the Serra Alta Formation throughout the basin, confirming correlation between Corumbataí and Teresina, and proposing that the upper Corumbataí and lower Rio do Rasto Formation may have been deposited contemporaneously, separated by local topographic highs.