(Fig. 1) Stable carbon and oxygen isotope ratios of foraminifera of ODP Hole 113-690B

A remarkable oxygen and carbon isotope excursion occurred in Antarctic waters near the end of the Palaeocene (~57.33 Myr ago), indicating rapid global warming and oceanographic changes that caused one of the largest deep-sea benthic extinctions of the past 90 million years. In contrast, the oceanic plankton were largely unaffected, implying a decoupling of the deep and shallow ecosystems. The data suggest that for a few thousand years, ocean circulation underwent fundamental changes producing a transient state that, although brief, had long-term effects on environmental and biotic evolution.

古新世（Palaeocene）末期（约5733万年前），南极海域发生了显著的氧碳同位素偏移事件，该事件指示了全球性快速变暖与海洋环境变化，进而引发了过去9000万年来规模最大的深海底栖生物灭绝事件之一。与之形成鲜明对比的是，海洋浮游生物基本未受影响，这暗示深浅层海洋生态系统发生了解耦。数据表明，在数千年的时间尺度内，海洋环流经历了根本性改变，形成了一种短暂的瞬态状态；尽管该状态持续时间较短，却对环境与生物演化产生了长期影响。