【摘要】 根据永暑礁小潟湖"南永3"井高分辨率的岩心材料,结合其高精度TIMS U系测年,系统研究了1 682 a B.P.以来环礁潟湖沉积柱样的有孔虫分类?类型与属种的组成,揭示了其垂直变化?有孔虫共48属62种,都是全新世-现代种,其中底栖有孔虫55种?其组成表征了印度洋-太平洋有孔虫区系和热带珊瑚礁相环境?即使由温凉水种浮游有孔虫偏多的时段所反映的表层水温也相对偏低,推测其变化幅度很小?底栖有孔虫茸刺距轮虫δ18O含量的变化曲线呈4峰4谷交替,反映了永暑礁海区近1 682 a以来的气候有4个凉期和4个暖期,同2 000a以来的全球气候变化周期一致?有孔虫种类的垂向变化也反映了海平面有些小变动?更多还原

【Abstract】 With the high distinguishable materials deposited in the small lagoon of Yongshu Atoll, and by the high-precision TIMS U-system dating, the taxonomy, type and composition of foraminifera in the core of Nanyong-3 well for the past 1682 years are systematically studied and their vertical changes are demonstrated. All the 48 genera and 62 species of foraminifera belong to Holocene-modern species, among which there are 55 species of benthon. The species composition shows Indian-Pacific foraminifera features and tropic coral reef environment charateristics. Even when the number of the warm-cool planktonical foraminifera species is more, which reflects a lower surface water temperature, the change magnitude is assumed to be not large. The δ18O content curve of the benthonical Calcarina hispida has 4 peaks and 4 nadirs, reflecting that there are 4 cool periods and 4 hot periods in the Yongshu Atoll area during the past 1682 years. This is accordant with the change cycle of the world climate in the past 2000 years. The vertical changes of foraminifera species also show that the sea level had small fluctuations.更多还原