What happens when the ocean is overheated? The foraminiferal response across the Paleocene-Eocene Thermal Maximum at the Alamedilla section (Spain)

Abstract

Research Article| September 01, 2010 What happens when the ocean is overheated? The foraminiferal response across the Paleocene–Eocene Thermal Maximum at the Alamedilla section (Spain) Laia Alegret; Laia Alegret † 1Departamento de Ciencias de la Tierra e Instituto Universitario de Investigación de Ciencias Ambientales de Aragón, Universidad de Zaragoza, 50009 Zaragoza, Spain †E-mail: [e-mail] Search for other works by this author on: GSW Google Scholar Silvia Ortiz; Silvia Ortiz 2Department of Earth Sciences, University College London, WC1E 6BT London, UK Search for other works by this author on: GSW Google Scholar Ignacio Arenillas; Ignacio Arenillas 1Departamento de Ciencias de la Tierra e Instituto Universitario de Investigación de Ciencias Ambientales de Aragón, Universidad de Zaragoza, 50009 Zaragoza, Spain Search for other works by this author on: GSW Google Scholar Eustoquio Molina Eustoquio Molina 1Departamento de Ciencias de la Tierra e Instituto Universitario de Investigación de Ciencias Ambientales de Aragón, Universidad de Zaragoza, 50009 Zaragoza, Spain Search for other works by this author on: GSW Google Scholar GSA Bulletin (2010) 122 (9-10): 1616–1624. https://doi.org/10.1130/B30055.1 Article history received: 19 Mar 2009 rev-recd: 08 Oct 2009 accepted: 08 Oct 2009 first online: 08 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Laia Alegret, Silvia Ortiz, Ignacio Arenillas, Eustoquio Molina; What happens when the ocean is overheated? The foraminiferal response across the Paleocene–Eocene Thermal Maximum at the Alamedilla section (Spain). GSA Bulletin 2010;; 122 (9-10): 1616–1624. doi: https://doi.org/10.1130/B30055.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The global warming and major perturbation of the global carbon cycle that occurred during the Paleocene–Eocene Thermal Maximum (PETM) have been investigated in the lower bathyal–upper abyssal Alamedilla section (Spain). Geochemical anomalies and dramatic faunal changes (including the globally recognized extinction event of deep-sea benthic foraminifera and the rapid evolutionary turnover of planktic foraminifera and calcareous nannofossils) are associated with the PETM at Alamedilla.Biotic changes in the plankton and benthos indicate environmental instability ∼11–14 k.y. before the onset of carbon isotope excursion that marks the Paleocene/Eocene boundary. The reorganization of the planktic ecosystem points to warm and oligotrophic conditions in surface waters during the earliest Eocene, whereas faunal and geochemical data indicate that the extinctions of benthic foraminifera occurred over an interval with a high CaCO3 content and oxic conditions at the seafloor. The proliferation of disaster taxa (Glomospira spp.) after the extinctions has been related to a potential source of isotopically light carbon in the western Tethys and North Atlantic.Significant changes in foraminiferal test size are documented across the PETM. We suggest that increased temperatures played an important role in benthic foraminiferal test size, increasing their metabolic rates and, consequently, their food requirements. Decreased planktic foraminiferal test size may be related to decreased nutrient availability or surface-water density. However, the differences in test size evolution among different species of both benthic and planktic foraminifera may be related to interspecific competition and ecological adaptations to direct or indirect consequences of the carbon addition during the PETM. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.