Pollen record and age determination of sediment core Fersina 2

Pollen analysis of samples taken from the core of the water well Fersina 2 (Adige Valley, Prov. Trento, NE Italy) did not reveal any indication of an interglacial or Holocene age of the uppermost 190 m in the sediment sequence deposited in the over-deepened Adige River Valley. The sediment sequence dates entirely from late-glacial times. Four radiocarbon ages of pieces of wood indicate that about 165 m of the upper part of the profile are of Younger Dryas age. The lower part of the sequence dates from the Allerød or Bølling/Allerød and a preceding cold phase, probably the Oldest Dryas. Accordingly the deposition of the sequence took about 2500 or 3500 years and was completed long before the onset of the Neolithic. Our results are in excellent agreement with findings in other formerly glaciated alpine valleys (e.g. the Traun, Salzach and Enns valleys in the Northern Alps). The final depth of the Fersina 2 well is 190 m. It is very likely that the sediment sequence found below this level in the nearby 423 m deep Fersina 1 well was also deposited after the deglaciation of the Adige Valley at the end of the last glacial period

Results of the radiocarbon age dating of wood fragments and sedimentation rates from three wells from the Adige Valley near the city of Trento (Northern Italy)

In three wells drilled in the south of the city of Trento into the sediments filling the valley of the Adige river at 11, 31 to 33, 130 and 139 m depth fragments of wood have been found and dated by radiocarbon method. From this dating results that the sedimentation rate in the valley of the Adige river was around 10,000 years B.C. extremely high, up to 130 mm/y and decreased after that lime rapidly to a rate of around 2 to 3 mm/y remaining rather constant until now. The high sedimentation rates around 10,000 years B.C. correspond to the climatic optimum that produced a rapid deglaciation in the Alps and an uplift of the Mediterranean Sea