Dati cronologici e stratigrafici su alcuni depositi continentali della Piana del Sele (Campania): i «conglomerati di Eboli»

Chronologic and stratigraphic data on some continental deposits of the Sele Plain (Campania): «conglomemti di Eboli»

Abstract

The term «conglomerati di Eboli» indicates a sequence of alluvial clastic deposits outcropping along the southern border of the Picentini Mountains and on the hills surrounding the inner margin of Sele Plain, among the towns of Eboli, Battipaglia and Salerno. These deposits are related with the Pleistocenic tectonic phases that caused the uplift of the Picentini Mountains and the depression of the Sele Plain-Salerno Gulf coastal graben. Several authors have already pointed out the relevance of the «conglomerati di Eboli» in the framework of the neotectonic evolution of the Campania Apennine. This paper provides a picture of the lithostratigraphic and chronologic characters of these deposits. Remarkable vertical changes within the sequence, marked by erosional disconformities, permit a definition of these deposits, in key of lithostratigraphic units, as a Group in which four formations are identified. They are moving from the bottom upwards: Fontana del Fico Formation, the Colle Mancuso Formation, the Castelluccia Formation and the S. Anna Formation. K/Ar radiometric datings of pyroclastic levels intercalated within the formations of the Eboli Group range between 1.52 and 0.99 M.A. and suggest, in agreement with other geological and geomorphological data, a Lower Pleistocene age for the Eboli Group. These dates are the chronological limits of the two main tectonic events responsable for the birth of sedimentary basin in which Eboli Group was accumulated and of its subsequent extinction for a tectonic uplift.