Intercalazioni vulcano-sedimentarie nella Formazione di Antognola: le sezioni "Rio Nespolo' e "M. Varano' (Oligocene Superiore, Appennino parmense)

Two coeval sections of Antognola Formation have been studied. The outcrops are located near Parma, in Ceno and Taro valleys. In both sections hemipelagic marls are associated with volcaniclastic beds. Pelitic sediments from Rio Nespolo section have been studied to characterize the main mineralogy and clay associations of terrigenous fine-grained sediments widespread in the Antognola Formation, up to the lower limit with the Ranzano Formation. Three different group of volcaniclastic beds are established: 1) zeolite-rich; 2) volcaniclastic arenites; 3) ash layers. The first 2 occur in the Rio Nespolo section, the 3rd in the M. Varano section. Because of characteristic field evidence of volcanogenic sediments and the occurrence of phases suitable for absolute age determination, these sediments can play an important role in stratigraphic studies and for chronostratigraphic time scale calibration