Late Eocene to Early Oligocene magnetostratigraphic chron boundaries of ODP Hole 119-744A (Table 1) ...
The earliest Oligocene (~33.5 Ma) is marked by a major step in the long-term transition from an ice-free to glaciated world. The transition, characterized by both cooling and ice-sheet growth, triggered a transient but extreme glacial period designated Oi-1. High-resolution isotope records suggest t...
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| Format: | Dataset |
| Language: | English |
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PANGAEA
1999
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| Online Access: | https://dx.doi.org/10.1594/pangaea.705531 https://doi.pangaea.de/10.1594/PANGAEA.705531 |
| Summary: | The earliest Oligocene (~33.5 Ma) is marked by a major step in the long-term transition from an ice-free to glaciated world. The transition, characterized by both cooling and ice-sheet growth, triggered a transient but extreme glacial period designated Oi-1. High-resolution isotope records suggest that Oi-1 lasted for roughly 400,000 yr (the duration of magnetochron 13N) before partially abating, and that it was accompanied by an ocean-wide carbon isotope anomaly of 0.75‰. One hypothesis relates the carbon isotope anomaly to enhanced export production brought about by climate-induced intensification of wind stress and upwelling, particularly in the Southern Ocean. To understand how this climatic event affected export production in the Southern Ocean, biogenic silica (opal) and carbonate accumulation rates were computed for the sub-polar Indian Ocean using deep-sea cores from ODP Site 744, Kerguelen Plateau. Our findings suggest that net productivity in this region increased by several fold in response to the ... : Supplement to: Salamy, Karen A; Zachos, James C (1999): Latest Eocene-Early Oligocene climate change and Southern Ocean fertility: inferences from sediment accumulation and stable isotope data. Palaeogeography, Palaeoclimatology, Palaeoecology, 145(1-3), 61-77 ... |
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