RADIOCARBON TIME SCALE FOR DEPOSITION OF HOLOCENE CALCAREOUS TUFA FROM POLAND AND INDIA (ORISSA).

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]