Deep-sea redox across the Paleocene-Eocene thermal maximum

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doi: 10.1002/2013GC005074
Author(s): Pälike, Cecily; Delaney, Margaret L.; Zachos, James C.
Author Affiliation(s): Primary:
Goethe-University Frankfurt, Institute of Geosciences, Frankfurt, Germany
Other:
University of California at Santa Cruz, United States
Volume Title: Geochemistry, Geophysics, Geosystems - G<sup>3</sup>
Source: Geochemistry, Geophysics, Geosystems - G>3`, 15(4), p.1038-1053. Publisher: American Geophysical Union and The Geochemical Society, United States. ISSN: 1525-2027
Note: In English. 95 refs.; illus., incl. 4 tables, sketch map
Summary: Large amounts of 13C-depleted carbon were released to the oceans and atmosphere during a period of abrupt global warming at the Paleocene-Eocene thermal maximum (PETM) (∼55 Ma). Investigations of qualitative sedimentologic and paleontologic redox proxies such as bioturbation and benthic assemblages from pelagic and hemipelagic sections suggest transient reductions in bottom water oxygen during this interval, possibly on a global scale. Here, we present bulk sediment manganese (Mn) and uranium (U) enrichment factors (EF) in Atlantic and Pacific deep-sea cores to constrain relative paleoredox changes across the PETM. Mn EF range from 1 to 9 in Atlantic sites, 1 to 35 in Southern Ocean sites, and are at crustal averages (EF = 1) in Pacific sites. U EF range from 1 to 5 in Atlantic sites, 1 to 90 in Southern Ocean sites, and are at crustal averages in Pacific sites. Our results indicate suboxic conditions prior to, during, and in the recovery from the PETM at intermediate depth sites in the Atlantic and Southern Ocean while the Pacific sites remained relatively oxygenated. The difference in oxygenation between the Atlantic and Pacific sites leads us to suggest the source for isotopically light carbon release during the PETM was in the Atlantic. Abstract Copyright (2014), American Geophysical Union. All Rights Reserved.
Year of Publication: 2014
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Actinides; Aliphatic hydrocarbons; Alkanes; Assemblages; Atlantic Ocean; Benthic taxa; Biogenic structures; Bioturbation; C-13; C-13/C-12; Carbon; Caribbean Sea; Cenozoic; Colombian Basin; DSDP Site 401; Deep Sea Drilling Project; Deep-sea environment; Demerara Rise; East Pacific; Eh; Equatorial Atlantic; Equatorial Pacific; Global change; Global warming; Hydrocarbons; IPOD; Isotope ratios; Isotopes; Kerguelen Plateau; Leg 113; Leg 119; Leg 165; Leg 198; Leg 199; Leg 207; Leg 208; Leg 48; Manganese; Marine environment; Marine sediments; Maud Rise; Metals; Methane; Nicaragua Rise; North Atlantic; North Pacific; Northeast Pacific; Northwest Atlantic; Northwest Pacific; ODP Site 1001; ODP Site 1209; ODP Site 1221; ODP Site 1258; ODP Site 1262; ODP Site 1263; ODP Site 1266; ODP Site 690; ODP Site 738; ODP Site 999; Ocean Drilling Program; Organic compounds; Pacific Ocean; Paleocene-Eocene Thermal Maximum; Paleogene; Sedimentary structures; Sediments; Shatsky Rise; South Atlantic; Southern Ocean; Stable isotopes; Tertiary; Uranium; Walvis Ridge; Weddell Sea; West Atlantic; West Pacific
Coordinates: S704954 S614837 E0030559 W0432706
S684114 S492407 E0855147 E0713936
N103000 N193000 W0650000 W0830000
N313400 N374800 E1624600 E1571500
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S290000 S270000 E0030000 E0013000
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Record ID: 2014098607
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom, Reference includes data supplied by, and/or abstract, Copyright, American Geophysical Union