Nannoplankton malformation during the Paleocene-Eocene Thermal Maximum and its paleoecological and paleoceanographic significance

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doi: 10.1002/2016PA002980
Author(s): Bralower, Timothy J.; Self-Trail, Jean M.
Author Affiliation(s): Primary:
Pennsylvania State University, Department of Geosciences, University Park, PA, United States
Other:
U. S. Geological Survey, United States
Volume Title: Paleoceanography
Source: Paleoceanography, 31(10), p.1423-1439. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. NSF Grant OCE-1416663. 105 refs.; illus., incl. sketch map
Summary: The Paleocene-Eocene Thermal Maximum (PETM) is characterized by a transient group of nannoplankton, belonging to the genus Discoaster. Our investigation of expanded shelf sections provides unprecedented detail of the morphology and phylogeny of the transient Discoaster during the PETM and their relationship with environmental change. We observe a much larger range of morphological variation than previously documented suggesting that the taxa belonged to a plexus of highly gradational morphotypes rather than individual species. We propose that the plexus represents malformed ecophenotypes of a single species that migrated to a deep photic zone refuge during the height of PETM warming and eutrophication. Anomalously, high rates of organic matter remineralization characterized these depths during the event and led to lower saturation levels, which caused malformation. The proposed mechanism explains the co-occurrence of malformed Discoaster with pristine species that grew in the upper photic zone; moreover, it illuminates why malformation is a rare phenomenon in the paleontological record. Abstract Copyright (2016), . American Geophysical Union. All Rights Reserved.
Year of Publication: 2016
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Algae; Aquia Formation; Atlantic Coastal Plain; Bass River; Bass River Site; Burlington County New Jersey; Cenozoic; Discoaster; Discoasteridae; Eocene; Gloucester County New Jersey; Leg 174AX; Lower Eocene; Marine environment; Marlboro Clay; Maryland; Microfossils; Morphology; Nannofossils; New Jersey; Ocean Drilling Program; Paleo-oceanography; Paleocene-Eocene Thermal Maximum; Paleoecology; Paleoenvironment; Paleogene; Phylogeny; Plantae; Shelf environment; South Dover Bridge; Talbot County Maryland; Tertiary; United States; Vincentown Formation; Wilson Lake; Wilson Lake Site
Coordinates: N384400 N394000 W0742600 W0760100
Record ID: 2017011804
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom