(Table DR1) Abundance of benthonic foraminifera in sediments from ODP Hole 113-690 ...

• Main Author: Thomas, Ellen
• Format: Dataset
• Language: English
• Published: PANGAEA - Publishing Network for Geoscientific and Environmental Data 2003
• Subjects: Methane hydrate; Southern Ocean
• Online Access: https://dx.doi.org/10.15468/spf4s9; https://www.gbif.org/dataset/792f74fa-f762-11e1-a439-00145eb45e9a

A mass extinction of deep-sea benthic foraminifera has been documented globally, coeval with the negative carbon isotope excursion (CIE) at the Paleocene-Eocene boundary, which was probably caused by dissociation of methane hydrate. A detailed record of benthic foraminiferal faunal change over ~30 k.y. across the carbon isotopic excursion at the Ocean Drilling Program Site 690 (Southern Ocean) shows that shortly before the CIE absolute benthic foraminiferal abundance at that site started to increase. 'Doomed species' began to decrease in abundance at the CIE by a few thousand years. After the extinction faunas were dominated by small species, which resemble opportunistic taxa under high-productivity regions in the present oceans. Calcareous nannofossils (primary producers), however, show a transition to more oligotrophic nannofloras exactly where the benthic faunas show the opposite. Plankton and benthos is thus decoupled. Possibly, a larger fraction of food particles reached the seafloor after the CIE, so ...