Foraminiferal assemblage and isotope studies of diatomaceous deposits collected under the subarctic convergence in the North Atlantic

北大西洋亚北极辐合下收集的硅藻沉积物的有孔虫组合和同位素研究

• 批准号: 21740361
• 负责人: YAMASAKI Makoto
• 金额: $ 2.25万
• 依托单位: Akita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21740361/
• 关键词: 地球史; 浮遊性有孔虫; 海洋前線; 北大西洋; 酸素同位体; 古海洋; 第四紀; 珪藻

Stratigraphic variation in foraminiferal assemblage and oxygen isotope was examined using the late Pleistocene diatomaceous deposits collected under the subarctic convergence in the North Atlantic. Oxygen isotope from surface and subsurface dwelling planktic foraminifers (Globigerina quinqueloba and Neogloboquadrina pachyderma sinistral) revealed that mat-forming diatom, Thalassiothrix longissima, occurred extremely abundant under cooler surface water condition, while it occurred commonly under warmer surface water one. The evidence suggests that deposition of the diatom mats is closely related to the surface water conditions.

利用北大西洋亚北极辐合带晚更新世沉积物研究了有孔虫组合和氧同位素的地层变化。表层和次表层浮游有孔虫（Globigerina quinqueloba和Neogloboquadrina pachyderma sinistral）的氧同位素研究表明，席状硅藻Thalassiothrix longissima在较冷的地表水条件下数量最多，而在较暖的地表水条件下数量最多。这些证据表明，硅藻垫的沉积与地表水条件密切相关。