The Annulata Event at the Pramosio Bassa section.

The Pramosio area was studied by Michele Gortani since the beginning of the 20th century. The Pramosio Bassa section was briefly described by Perri et al. (1998) and Spalletta & Perri (2001). Mossoni (2014) studied magnetic susceptibility, magnetic hysteresis and major elements content of the section. The results of this study fit very well with the palaegeographic position of the Carnic microplate during the Late Devonian hypothesized by Schönlaub (1993) and von Raumer & Stampfli (2008). According to these Authors the Carnic microplate was located far away from land. Mossoni (2014) demonstrated that during the limestone deposition the detrital input was scarce, this is consistent also with the transgressive event considered as triggering cause of the Annulata radiation. All the studied parameters show values consistent with the identification of the Upper Annulata Event in correspondence of the level of sample PB5a (Mossoni 2014). In the Carnic basin a general transgressive tendency from the Lower marginifera Zone to the base of the Lower postera Zone (Palmatolepis marginifera marginifera–Polygnathus styriacus zones of Spalletta et al. 2017) was inferred by Perri & Spalletta (2000) based on conodont biofacies analysis. Hartenfels & Becker (2016) report that the level yielding a mass occurrence of Prionoceras (bed of sample PB5a) can be considered as an equivalent of the Wagnerbank of Thuringia. According to Hartenfels & Becker (2016) the goniatite-rich limestone of the Wagnerbank represents a regressive phase in the highest part of the annulata Zone (UD IV-A).