QUANTITATIVE MICRO-PIXE AND MICRO-PROBE ANALYSIS OF OSTRACODE SHELLS TO RECONSTRUCT THE PALEOENVIRONMENT

The micro-probe setup of Fudan University has been used to study the trace elemental composition and distribution of ostracode shells. The process involved in trace elemental analyses of ostracode shells are described in detail. Stenocypris derupta Vavra, Dolerocypria mukaishimensis okubo and Tanella opima Chen, three kinds of ostracodes are analyzed. In this study, we concentrate on the relationships between molar ratios of Mg/Ca and temperature, and between molar ratios of ME/Ca and salinity of host water. We have found the molar ratios of Mg/Ca in shells are positively correlated with the temperature of the host water, but negatively correlated with the salinity of host water. The ostracode fossils from Shengli oil field are also analyzed, and the results are reported too. The elemental distributions of ostracode are also measured. We found that the element distributions of newly formed ostracode shell have the same pattern, but ostracode fossils often have an obvious specific distribution, different elements have different distribution.