Volume of Abstracts - Università degli Studi di Milano

5 th Int. Workshop on Ice Caves (IWIC – V)
Barzio (LC), Valsassina, Grigna and Milano, September 16 – 23, 2012
Volume of Abstracts
TWO MILLENNIA OF NATURAL TO ANTROPOGENIC EFFECTS IN
TRANSYLVANIA FROM FOCUL VIU ICE CORE
Maggi V. 1 , Turri S. 2 , Bini A. 3 , Perşoiu A. 4 , Onac B. 4 , Stenni B. 5 & Udisti R. 6
1 Environmental Sciences Dept., University of Milano-Bicocca, Italy
2 GeoSFerA Studio Associato di Geologia, Varese, Italy
3 Earth Sciences Dept., University of Milano, Italy
4 Dept. of Geology, University of South Florida, 4202 E. Fowler Avenue, SCA 528, Tampa, 33620, Fl,
USA
5 Geosciences Dept., University of Trieste, Italy
6 Chemistry Dept., University of Florence, Italy
The 8.26 m of ice core drilled in Focul Viu Ice Cave (Apuseni Mountains,
Romania) represent one of the longest records from hypogean ice deposits.
A set of 8 radiocarbon dates was done on organic materials found in the ice
cores at different depth, and estimate of the age at 6.84 m depth, the
bottommost samples, is of 1752±66 B.P. (calibrated date). Major ions were
measured for atmospheric composition record reconstructions. Some huge
nss-SO4 2- (no-sea-salt sulphates) spikes were preliminary related with
historical well-known explosive volcanic events, with an improve of
age/depth time scale. Using both 14 C dates and volcanic spikes, was
evaluates the variability of the accumulation rate of ice deposits, that show
a mean value for the entire ice core of 34,8 cm/century of ice. A detailed
behaviour was observed among different stratigraphic periods, with special
emphasis to the Middle Age period with a huge accumulation, 3 time the
following period 1400-1800. The last 2 centuries were characterized by the
industrial impact on the atmospheric composition. Using the record of
Ammonia, that can be related to biomass burning from forest clearance or
agriculture practise, will describe the influences of the anthropogenic
activities in the Transylvania during the last two millennia. Interpolating
the accumulation rate of the deeper part of the ice core, below the 6,84 m
depth, was estimated the age of the bottom ice at 8,26 m depth of at
around the 2600 B.P. (V century A.C.), at the beginning of Roman period.
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