Palinostratigrafia dei bacini intermontani dell'Appennino nord-occidentale

Abstract

Palynological investigations, carried out on the basal lacustrine sediments of the upper Neogene intermontane continental basins of the north-western Apennines (Magra and upper Taro valleys), show the presence of a rich palynoflora and complex vegetational successions. This paper highlights prominents paleofloral and palynostratigraphic features, plotting the results of pollen analyses in synthetic diagrams. Several pollen assemblages can be recognized; among these, two assemblages of "tertiary" elements are very characteristic: the Taxodiaceae assemblage (Taxodium-type, Sciadopitys, Sequoia-type, Nyssa, Myrica, ...) and the tropical-subtropical assemblage (Symplocos, Sapotaceae, Clethraceae/Cyrillaceae, Rhoiptelea, Reevesia, Itea, ...). Sequence of floral extinctions supports a succession of vegetal biozones which may be used to palynostratigraphically correlate the various pollen sequences and to set them stratigraphically within the Plio-Pleistocene continental stages. The results improve the stratigraphic scheme of paieoflora evolution for the northern Italy during upper Neogene-early Pleistocene times and enhance knowledge on the paleogeography and tectonic evolution of the northwestern Apennines continental basins.