Biogeography of the Late Paleocene Benthic Foraminiferal Extinction

作者：Ellen Thomas · 年份：1998 · DOI：10.25438/wes02.32805974 · 被引用次数：176 · 研究领域：Geology and Paleoclimatology Research、Marine Biology and Ecology Research、Isotope Analysis in Ecology

During the Late Paleocene Thermal Maximum (LPTM) benthic foraminifera at middle bathyal and greater depths suffered extinction of 30-50% of species during a few thousand years. Extinction was less severe at neritic to upper bathyal depths where temporary changes in faunal composition prevailed. Pre-extinction deep-sea faunas were cosmopolitan and diverse and contained heavily calcified species. Immediate post-extinction faunas were more variable geographically exhibited low diversity and were dominated by thin-walled calcareous or agglutinated taxa possibly because CaCO3 dissolution increased globally from neritic to abyssal depths just before the extinction. These assemblages were dominated either by long-lived taxa such as Nuttallides truempyi or by buliminid taxa the latter accompanied by agglutinants in some areas. Faunas dominated by N. truempyi were common in the South Atlantic and at lower bathyal through upper abyssal depths in the Indian Ocean and might indicate oligotrophic conditions as well as increased corrosiveness. Buliminid-dominated faunas might indicate high rates of deposition of organic matter or low-oxygen conditions. Such faunas were common globally along continental margins and locally co-occurred with sedimentologic or planktonic faunal indicators of high productivity. In the bathyal central Pacific however buliminid dominated faunas co-occurred with planktonic faunas suggesting oligotrophy and they could reflect low-oxygen conditions resulting from sl...