The Carnian Pluvial Episode as a key interval for large-scale correlations through the Lagonegro-Imerese-Sicanian Basin (Southern Italy)

The Lagonegro-Imerese-Sicanian Basin deposits form thick Meso-Cenozoic successions arranged in different stacked tectonic units. The basin opened along the northern margin of the African Plate and, during the Meso- zoic, developed as a pelagic to hemipelagic domain enclosed between the coeval Apennine (or Panormide) and Apulian carbonate platforms. Sedimentation in the basin was mainly provided by the platform margins and/or siliceous/calcareous ooze fallout. As expected, sedimentary supply from the adjacent carbonate highs was signifi- cant in the proximal sectors and progressively diminished toward the distal, axial part of the basin. Given this close platforms - basin connection, climatic or tectonic changes affecting the platform margins are likely to be recorded in the basinal settings as distinctive stratigraphic intervals or stratigraphic gaps, providing reliable markers for regional-scale correlation and paleogeographic reconstructions. The Carnian Pluvial Episode (CPE), occurring in the lower part of Calcari con Selce Formation (Upper Triassic), is suggested as a marker horizon across the entire Lagonegro-Imerese-Sicanian Basin. This interval, already rec- ognized in the proximal sector of the basin, was unknown for the distal portion of the basin so far. The identifica- tion of the Sorgente Acero Unit, a peculiar stratigraphic interval at the base of the Calcari con Selce Formation in the distal Lagonegro sector, as the equivalent of the CPE, enabled regional-scale correlations and a revision of the paleogeographic reconstructions of the basin during the Late Triassic. The attribution of the Sorgente Acero Unit to the CPE has been achieved thanks to integrated paleontological studies on palynomorphs, radiolarians and conodonts.