Faunal evidence for reduced productivity and uncoordinated recovery in Southern Hemisphere Cretaceous/Paleogene boundary sections

Journal article


Publication Details

Author(s): Kießling W
Journal: Geology
Publisher: Geological Society of America
Publication year: 2007
Volume: 35
Journal issue: 3
Pages range: 227-230
ISSN: 0091-7613


Abstract


The mass extinction at the Cretaceous-Paleogene boundary is generally explained by a severe crisis in primary productivity, following a catastrophic bolide impact. Consistent with this scenario, Danian mollusk-dominated benthic shelf ecosystems of southern middle paleolatitudes (Neuquén Basin, Argentina) are characterized by (1) a stratigraphically limited low in macrofossil abundances; (2) an increase in starvation-resistant, nonplanktotrophic deposit feeders and chemosymbionts; (3) a reduction in the average body size of individuals; and (4) individuals with inactive lifestyles being more common than in the late Maastrichtian. Return to pre-extinction conditions of the various synecological attributes occurred over unequal time spans, indicating that recovery was uncoordinated with respect to ecological traits. Global comparison of ecological patterns suggests that reduced food supply (1) was a controlling factor in both hemispheres; (2) affected macrobenthic marine faunas at various distances from the Chiexulub impact site; and (3) was more effective in silicielastic environments as compared to oligotrophic carbonate settings. © 2007 Geological Society of America.



FAU Authors / FAU Editors

Kießling, Wolfgang Prof. Dr.
Lehrstuhl für Paläoumwelt

Last updated on 2018-11-08 at 01:09