INDICATION OF CLIMATIC CHANGES THROUGH THE INORGANIC COMPONENTS IN DIATOMS (HOVSGOL).

Compositions of diatom valves have been for the first time obtained for the intervals of their distribution in two sedimentary sampling depth using the EPMA technique developed earlier. The investigations were performed using electron microscopes Quanta and microprobe JXA8200. The comparison of the inorganic element concentrations suggested some regular features in the change of diatom valve composition throughout the sampling depth. The sampling intervals which contain poorly-preserved valves show higher carbon and lower SiO2 contents. The comparison with the literary spore-pollen analysis exhibits the correlation between steppe/forest interface and areas with high and low SiO2 content. Such correlation cannot be random and most likely indicates the prospects of using this procedure. The obtained data can be used as indicators of climatic changes at certain periods of diatoms' life (cold or warm). [ABSTRACT FROM AUTHOR]