Aragonite content, stable oxygen isotopes of Globigerioides ruber, and age of ODP Site 166-1006 sediments@en

The 1.4-m.y.-long stable oxygen isotope record of Site 1006 in the low-latitude North Atlantic Ocean shows large glacial/interglacial amplitude changes caused by a combination of temperature and salinity fluctuations. A trend of increased sea-surface temperatures during the interglacial periods is present in the record beginning at isotopic Stage 11 and ultimately leading to the lightest d18O values in isotopic Stages 9, 5, and 1. Maximum d18O values are recorded during glacial isotopic Stages 6 and 8. Stable isotopic variability increased during the Brunhes Chron at the 100-ka time scale. The large amplitude changes can best be explained by global and regional ocean circulation changes. Increased strengthened return flow of warm salty water from the Pacific may have occurred during interglacial periods since isotopic Stage 11, which was largely reduced during glacial periods. The large climate fluctuations had a profound effect on the shallow-water carbonate production of the Great Bahama Bank. The aragonite content of the sediments shows fluctuations that follow the d18O record. The leeward side of the Great Bahama Bank received increased input of platform material during sea-level highstands when the sea-surface waters were warm.北大西洋低纬度海域1006站位的140万年时长稳定氧同位素记录，展现了由温度与盐度波动共同引发的显著冰期-间冰期振幅变化。该记录自氧同位素阶段11起，呈现出间冰期海表温度升高的趋势，并最终在氧同位素阶段9、5及1中达到最轻的d18O值。冰期氧同位素阶段6与8中则记录了最高的d18O值。布容正向极性时（Brunhes Chron）内，稳定同位素的变异幅度在10万年时间尺度上有所增强。这类大幅振幅变化最佳的解释为全球及区域海洋环流的改变。自氧同位素阶段11以来的间冰期，可能出现了源自太平洋的暖咸水回流增强的现象，而冰期时该回流大幅减弱。剧烈的气候波动对大巴哈马滩的浅水碳酸盐沉积生产产生了深远影响。沉积物中的文石（aragonite）含量呈现出与d18O记录相契合的波动特征。当海表水体温暖、海平面处于高位期时，大巴哈马滩的背风侧接收了更多的台地物质输入。