STRATIGRAPHIC AND TECTONIC FEATURES OF THE MIDDLE PLEISTOCENE SEDIMENTARY AND VOLCANIC DEPOSITS IN THE AREA OF ROME (ITALY)

The analysis of a large number of stratigraphic logs From boreholes, a s well as an extensive field survey, suggests that the Middle Pleistoc ene sedimentary deposits in the area of Rome can be subdivided into tw o groups, each one characterised by a different stratigraphy and tecto nic setting: a north-eastern sector, corresponding to the eastern urba n area of Pome, and a south-western sector, corresponding to the Ponte Galeria area. In the north-eastern sector, the distribution of sedime nts is influenced by vertical block faulting showing a predominantly n orth-south trend, superimposed on a Middle Pleistocene NE-SW extension al tectonic domain. In the south-western sector, we suggest that the ' 'Ponte Galeria Formation'' auct. can be subdivided into two deposition al sequences that can be linked to isotope stages 19 and 21. In additi on, a sedimentary hiatus is proposed at the top of the Ponte Galeria s equence. It corresponds to the deposition of a continental succession in the north-eastern sector before the emplacement of pyroclastic depo sits From the Colli Albani and Sabatini volcanic Districts. The correl ation between these two depositional sequences, that have been identif ied, and the oxygen isotope time scale allowed us to extend our invest igation across to the urban area of Pome, where we have recognised six sedimentary cycles, all of Pleistocene age, which have been tentative ly related to particular isotopes stages. (C) 1998 INQUA/Elsevier Scie nce Ltd. All rights reserved.