COMBINING MICRO-PIXE AND DELTA-O-18, DELTA-C-13 ISOTOPE ANALYSES TO RECONSTRUCT LACUSTRINE PALEOENVIRONMENT

Combining micro-PIXE and delta(18)O, delta(13)C isotope analyses, we h ave analyzed 199 fossil ostracodes from Donggou and Xiaodukou-Haojiata i sections of Nihewan basin, and grey statistics has been applied to a nalyze the data from these analyses. We have got the following results . (1) The values of delta(18)O and delta(13)C are highly correlated, a nd they are mainly affected by the paleosalinity variation of host wat er. (2) The variation of Mg/Ca ratio is much different from those of d elta(18)O and delta(13)C. Factor analysis in the behavior space of del ta(18)O, delta(13)C and Mg/Ca shows the Mg/Ca molar ratio is positivel y correlated with the paleotemperature of host water. (3) The change c haracteristics of paleotemperature and paleosalinity revealed by facto r-score curves are in agreement with those determined by sedimentologi cal and paleontological study, and the combination style of these curv es indicates the paleoclimatic change characteristics. (C) 1997 Elsevi er Science B.V.