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14C concentration measurements together with carbon and oxygen stable isotope analysis in calcareous tufa give possibilities for reconstruction of time scale and palaeoclimatic conditions of sedimentary processes. Results of isotope examinations of 2 profiles with organic and tufa sediments from Eastern Poland and 8 calcareous tufa sites from Eastern India (Orissa) are given. A systematic error of 14C conventional age of carbonate fraction of tufa samples as reservoir age (TR) was estimated. The TR values of different type of tufa sediment are determined by stream water energy. On the basis of known experimental dependence between TR and δ13C for tufas deposited in high, average and low energy water, unknown values of TR and corrected 14C ages (TCCA) were calculated for samples from India tufa sites. Continuous deposition of organic and carbonate sediments in Polish profiles give the possibility to calculate the approximated TCCA ages on the basis of dependence between TCCA and a sample depth in a profile, and time scale reconstruction of δ13C and δ18O changes in carbonate fraction of tufa samples during the whole Holocene. [ABSTRACT FROM AUTHOR]

Measurements of δ18O and δ13C in tufa samples dated by 14C method have been used to reconstruct climatic changes in Southern and Eastern Poland and in Eastern India (Orissa) for the last ca 13,500 years. Stable isotope time record δ18O in calcareous tufa profiles can be interpreted as palaeoclimatic record if dependence between oxygen isotope composition and temperature for the specific climatic region is known. Estimated sedimentation temperatures of calcareous tufas from Polish sites indicate the mean year of air temperatures during the last 12,000 years and mean winter and summer temperature for Orissa state, using stable isotope analysis for calcareous tufa from Indian sites. The estimated temperatures have real values, comparable with contemporaneous sedimentation temperature. The characteristic trend of the temperature changes increasing for Poland and decreasing for Orissa, since the beginning of the Holocene till today, can be observed with climatic optimum ca 5 000- 6000 BP synchronous in both countries. [ABSTRACT FROM AUTHOR]