LATE QUATERNARY SHORELINES IN SOUTHERN CILENTO (MT. BULGHERIA): MORPHOSTRATIGRAPHY AND CHRONOLOGY

Abstract

A detailed geological and geomorphological survey of shorelines and continental deposits, cropping out along the carbonate coast
between the Mingardo river mouth and Cala degli Infreschi bay, was carried out. Several erosional indicators of paleo-sea level stands
were collected such as notches, wave-cut terraces and upper limits of Lithophaga burrows. Littoral sediments are often present on with these erosional features and are made up of sands and conglomerates which locally contain mollusc shells, red algae and corals.
These evidence have been preserved along paleo-sea cliffs or inside coastal caves of prevalent karstic origin.
The continental deposits, often associated with marine successions, are represented by eolian and colluvial deposits, paleosols and,
inside the coastal caves, by speleothems and graviclastic breccias. In many localities these continental deposits contain lithic industries
of palaeolithic age which can be considered as lower or upper chronological limits for the associated shorelines.
Geomorphological cut-cross relations, stratigraphic position and altimetrical correlation among continental and marine deposits were
analysed in order to recognise both their relative chronology and the phases of coastal morphogenesis, linked to the interaction
between sea level fluctuations and tectonic uplift. Mineralogic analysis on paleosols was also carried out for paleoenvironmental reconstructions. Moreover, Th/U datings of speleothems, which directly cover or are buried by marine deposits, were carried out in order to give chronological constrains for the reconstruction.
At least six orders of Middle Pleistocene marine terraces are present between 75 and 15 m a.s.l.; the complete flight of these terraces is
only well preserved along the western part of the Mt. Bulgheria coast. Between 10 e 3.5 m a.s.l. we recognised three other paleo-sea
level stands, the youngest of which is represented by fossiliferous conglomerates and sands. The Th/U age of the speleothem (90 ka
BP) which is buried by these marine deposits and the Th/U age of the speleothem which cover the marine sands (50 ka BP) allowed us
to ascribe this shoreline to the OIsS 5a. This correlation is supported by the mousterian age of the graviclastic breccia lying on them.