Paleoclimatic record of the past 22,000 years in Venice (Northern Italy): Biostratigraphic evidence and chronology

Four new 20-m cores drilled (2000-2001) in the historical city centre of Venice, provided new data on Late Pleistocene and Holocene deposits from pollen biostratigraphy, foraminiferal associations and 10 new C-14 dates. About 22,000 years ago, alluvial deposits were laid down in an environment characterized by intense flooding with episodes of swamp conditions between 22,410 +/- 130 and 20,830 +/- 130 years BP. This full glacial phase was followed by one of prevailing fine materials between 19,790 +/- 120 and 19,280 +/- 120 years BP. The Flandrian marine invasion occurred 5520 +/- 50 years BP, and gave rise to a layer about 5 m thick, in which the foraminiferal associations show ancient channels and buried salt marshes. Palynological analysis indicates two different pollen zones: one is full glacial, with two phases of climatic warming going back to the Tursac and Laugerie interstages; the second corresponds to Holocene lagoonal deposits. The main peat layers represent episodes of stagnation in stadial conditions. The two warm interstages lasted a few centuries. Above the Laugerie interstage, peaty remains in continental sands underlying the Holocene lagoonal deposits of Atlantic age date back to 9173 +/- 80-7165 +/- 60 years BP, showing the presence of the Early Holocene. (c) 2005 Elsevier Ltd and INQUA. All rights reserved.