Evoluzione geomorfologica della Pianura di Piombino in Toscana

Geomorphological evolution of the Piombino plain. Tuscany

Abstract

Following a new geologic survey and the results from about 170 drillings and 200 geoelectric surveys, the geological and geomorphological evolution of the Piombino plain is discussed. The main conclusions of this study concern: – the presence of three sedimentary sequences in the whole Palmentello-Lumiere plain. Every sequence is characterized, at the bottom, by sediments of submerged beach or at least, of marine coastal facies. At the top, the sequence is characterized by emerged beach of dunes or littoral deposits still feeded to eolian debris from the coast. All these sequences are of Late Pleistocene age; – the location of the buried faults in the Piombino plain permitting the recognition of a NW-SE trending graben and of an important SW-NE oriented dislocation; – a more detailed reconstruction of the paleo-geographic evolution during the Pliocene. This reconstruction is also based on the new data presented by BARTOLINI & alii (1989); – the presence of a geo-physical buried surface. Such a surface is very important to understand the geo-morphological evolutiun of the studied area.