Stable isotope ratios and foraminiferal abundance of sediment cores from the Western Iberian Margin ...
Rapid climate changes at the onset of the last deglaciation and during Heinrich Event H4 were studied in detail at IMAGES cores MD95-2039 and MD95-2040 from the Western Iberian margin. A major reorganisation of surface water hydrography, benthic foraminiferal community structure, and deepwater isoto...
Main Authors: | , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
PANGAEA
2003
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Subjects: | |
Online Access: | https://dx.doi.org/10.1594/pangaea.733303 https://doi.pangaea.de/10.1594/PANGAEA.733303 |
Summary: | Rapid climate changes at the onset of the last deglaciation and during Heinrich Event H4 were studied in detail at IMAGES cores MD95-2039 and MD95-2040 from the Western Iberian margin. A major reorganisation of surface water hydrography, benthic foraminiferal community structure, and deepwater isotopic composition commenced already 540 years before the Last Isotopic Maximum (LIM) at 17.43 cal. ka and within 670 years affected all environments. Changes were initiated by meltwater spill in the Nordic Seas and northern North Atlantic that commenced 100 years before concomitant changes were felt off western Iberia. Benthic foraminiferal associations record the drawdown of deepwater oxygenation during meltwater and subsequent Heinrich Events H1 and H4 with a bloom of dysoxic species. At a water depth of 3380 m, benthic oxygen isotopes depict the influence of brines from sea ice formation during ice-rafting pulses and meltwater spill. The brines conceivably were a source of ventilation and provided oxygen to the ... : Supplement to: Schönfeld, Joachim; Zahn, Rainer; de Abreu, Lucia (2003): Surface to deep water response to rapid climate changes at the western Iberian Margin. Global and Planetary Change, 36(4), 237-264 ... |
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