South Kong,. Sonko A Well Cretaceous Stable Isotope And Trace Element Study Of The Mid Ostracods Shell

This paper from the Cretaceous Continental Scientific Drilling of China to obtain a continuous, high-resolution, less damaged by the Cretaceous continental strata , with ostracods fossil shells were used to experiment by stable isotopes and trace elements in high-precision determination based on identify the biological classification, in order to find high-resolution mid-Cretaceous paleoenvironment, paleoclimate information of Songliao Basin.In this study, 1003 core samples were collected, found 557 fossils of ostracods, identified the 15 fossil assemblage, the measured carbon and oxygen isotopes 252 ,and 189 trace element ratio data. Finishing in the analysis, discussion, draw the following conclusions:1)SK-1 by ostracods fossi shell preserved of long-term, continuous climate history, demonstrates very study value of carbon and oxygen stable isotopes and trace elements ratio sequence.That could provides a good sequence standards for China even global cretaceous continental research.2) The Oxygen isotope data in Qingshankou F.2,F.3 reflects the highest temperature sign here, and cooling since then. The Oxygen isotope records in Songliao basin seemingly track the corresponding contemporaneous isotopic marine records. At the same time, the oxygen isotopes was affect by chemical composition of water.3) Carbon isotope are revealed geological events at least five times . One of the biggest events in the negative shift reaction of Songliao Basin should affect by the lake shrink, then, the creature in lake mass extinction, organic carbon geobiology decrease relatively ,large increase 12C dissolved into the water,δ13C in the water in the short-term drop sharply finally.4)Temperature,salinity and mineral deposits are common control of Sr/Ca and Mg/Ca ratio. That reflect Qingshankou F. 2, 3 by low salinity increases, the reduction process, Yaojia F. salinity lower than whole Qingshankou F2,3. Yaojia F2 salinity relative stability. And gradually increased in Yaojia F3. Nenjiang F1,2 appeared the lowest data. That suddenly, rapid changes may be cooling effect, and may affect by oxidation-reduction environment, pH change and deposition of carbonate.5)Put the geochemical test data from ostracodes fossil shell to Fourier transform. The spectrum diagram from FFT shows that transformation parameters n will not change the spectral curve graphics changes in the large amplitude. Frequency corresponding changes may be due to excessive spacing samples and sampling not enough. Oxygen isotopes and carbon isotopebe are subjected to a periodic function, and the strong influence of oxygen isotopes influence than 10 times higher carbon isotopes. Various microelement by different laws on the cycle is weak, the common influence function alternately. Trace elements ratio spectrum diagrams clearly eliminate a lot of noise.