Stable isotopes of Holocene calcareous tufa in southern Poland as paleoclimatic indicators

Abstract

The isotopic composition of oxygen in freshwater calcareous tufa seems to be a sensitive indicator of past climatic changes. Results of measurements of δ c 18O and δ c 13C in tufa samples dated with the 14C method are used to reconstruct Holocene climatic changes in southern Poland. Values of δ c 18O obtained on tufa samples from four sites (Raclawka, Rzerzuŝnia, Trzebienice, Sieradowice) representing different hydrodynamic conditions of tufa sedimentation seem to form a selfconsistent series. These values, with some simplifying assumptions concerning the course of tufa sedimentation, were therefore used to estimate mean annual temperatures in the interval ca. 9500-2000 yr B.P. When the resulting curve of thermal changes in southern Poland is compared with changes of deposition and erosion of tuffaceous sediments and with results of other methods of reconstruction of paleoclimate in central Europe, a reasonable agreement among the different specific methods is seen.