Coccolithophorid (calcareous nannofossil) fossilization process response to paleoceanographic environmental reconstruction

如何提取化石组合的海洋条件，对重建古海洋环境具有重要意义。利用捕集器样品，阐明了球石藻组合随季节变化的规律。澄清了沉积过程中组合的转变。此外，还对圈闭位置的表层沉积物中球粒岩藻群落进行了分析，阐明了组合的季节变化、垂直运移过程和溶解过程之间的关系。从西北太平洋1371m和4787m深度系泊泥沙捕集器实验结果可以看出：通过对该海域常年圈闭的分析，认为优势种huxleyi Emiliania、Gephyrocapsa oceanica和Florisphaera profunda为水平组合。因此，在对该海区表层沉积物分类群进行环境分析时，期望地表年平均反映更多的冰水是合适的。另一方面，由于捕集器在4 - 5月识别出上层球虫的数量增加，表明该物种在表层沉积物中表明了4 - 6月生物产量较高的时期。诱捕试验证实了易碎鲕粒的增加与营养增加的周期有关。对近25万年赤道太平洋球石藻沉积过程的季节变化与表层沉积物组合的关系进行了详细的环境变迁分析。在第1阶段、第3阶段、第5阶段和第5/6阶段，该物种的生产频率有所增加。由于捕集器试验的物种增加季节在冬季是有限的，因此这种物种增加周期在该沉积物芯中反映冬季的影响更强烈。根据沉积过程的结果，考虑到球石藻的特征组合随季节的变化，各区域的代理分类群特征明显不同，可以对古海洋环境变化进行详细的分析。少

It is important how to draw out the oceanic condition of the fossil assemblage to reconstruct the paleooceanographical environment. The coccolithophorid assemblages change according to the seasonal change is clarified by using the sediment trap samples. The assemblages transition by the deposition process is clarified. In addition, it aimed to analyze the coccolith thanatocoenoses in the surface sediment is analyzed in the trap location, and to clarify the relation among the assemblages seasonal change, the vertical transport process, and the dissolution process.It became clear the following from the sediment trap experimentation result of mooring at depth 1371m and 4787m in northwest Pacific Ocean. It has been understood that the dominant three species, Emiliania huxleyi, Gephyrocapsa oceanica and Florisphaera profunda, from the analysis of the trap during year in this sea area are leveled assemblages. Therefore, it turned out that expecting the environment of the annual mean of surfa … More ce water would be reflected was appropriate in the environmental analysis with these taxa in the surface sediment in this sea area. On the other hand, because Coccolithus pelagicus was recognized increasing from April to May in the trap, it turned out that this species in the surface sediment indicated the period when the biological production from April-June was high.Increase of Oolithotus fragilis had been confirmed the increasing nutrients periods from the trap experiment. Detailed environmental transition analysis was done about the relation between the seasonal variation of the deposition process of the coccolithophorid and the surface sediment assemblages in the equator Pacific Ocean during past 250,000 years. The increase in the production frequency of this species was recorded in the oxygen stages 1, 3, 5, and 5/6 boundary. This species of increase periods were suggested to be a result of reflecting the influence in winter more strongly in this sediment core, because this species of increase season by the trap experiment has been limited in winter.The characteristic of the proxy taxa became clear different in each region and the paleooceanographical environmental variation's detailed analysis was enabled based on the result of the depositional processes and the considering of the characteristic coccolithophorid assemblages with the seasonal change. Less