Benthic foraminifera analysis of two sediments cores from the northern Cape Basin in the eastern South Atlantic Ocean

Two late Quaternary sediment cores from the northern Cape Basin in the eastern South Atlantic Ocean were analyzed for their benthic foraminiferal content and benthic stable carbon isotope composition. The locations of the cores were selected such that both of them presently are bathed by North Atlantic Deep Water (NADW) and past changes in deep water circulation should be recorded simultaneously at both locations. However, the areas are different in terms of primary production. One core was recovered from the nutrient-depleted Walvis Ridge area, whereas the other one is from the continental slope just below the coastal upwelling mixing area where present day organic matter fluxes are shown to be moderately high. Recent data served as the basis for the interpretation of the late Quaternary faunal fluctuations and the paleoceanographic reconstruction. […]对采自南大西洋东部开普盆地北部的两支晚第四纪沉积物岩芯开展了分析，检测其底栖有孔虫（benthic foraminifera）组分与底栖稳定碳同位素组成。所选岩芯站位均处于现今北大西洋深层水（North Atlantic Deep Water, NADW）覆盖范围内，可同时记录深水环流的过往变化。但两处区域的初级生产水平存在差异：其中一支岩芯采自营养盐匮乏的沃尔维斯海岭（Walvis Ridge）区域，另一支则取自沿岸上升流混合区下方的大陆坡，该区域现今有机质通量（organic matter fluxes）被证实处于中等偏高水平。近期研究数据为晚第四纪动物群波动的解读以及古海洋学重建工作提供了依据。[…]