Selective extinction and survival across the Cretaceous/Tertiary boundary in the northern Atlantic Coastal Plain

Journal Article · Tue Oct 01 00:00:00 EDT 1991 · Geology; (United States)

DOI:https://doi.org/10.1130/0091-7613(1991)019<0967:SEASAT>2.3.CO;2· OSTI ID:5996741

Gallagher, W B ^[1]

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1. New Jersey State Museum, Trenton (United States)

The inner Atlantic Coastal Plain in New Jersey and the Delmarva Peninsula is underlain by an Upper Cretaceous-lower Tertiary sequence of marine and paralic sand, clay, and glauconitic beds. Campanian, Maastrichtian, Danian, and Thanetian deposits are especially fossiliferous and yield a succession of marine faunas that reveal a pattern of selective extinction and survival across the Cretaceous/Tertiary (K/T) boundary in this area. Cretaceous benthic invertebrate communities are dominated by oysters and other semi-infaunal and infaunal molluscs with planktotrophic larval stages. These are replaced in the Danian by brachiopod-dominated communities that are composed of epifaunal benthos with a variety of nonplanktotrophic reproductive strategies. A similar pattern is observable in the nektonic cephalopod populations in this sequence; the typical ammonites of the Cretaceous became extinct at the K/T boundary, whereas the nautilids survived. Ammonites are thought to have had a planktotrophic larval stage, whereas nautilids are known to lay large lecithotrophic eggs. This pattern of differential survival is attributed to the planktonic population crash at the K/T boundary which placed planktotrophically reproducing species at a disadvantage while favoring the varied groups that practiced alternative reproductive strategies.

• OSTI ID: 5996741
• Journal Information: Geology; (United States), Vol. 19:10; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
CRETACEOUS PERIOD
BOUNDARY CONDITIONS
GEOLOGIC FORMATIONS
PALEONTOLOGY
NEW JERSEY
TERTIARY PERIOD
AQUATIC ORGANISMS
DEATH
FOSSILS
REPRODUCTION
STRATIGRAPHY
SURVIVAL CURVES
CENOZOIC ERA
DEVELOPED COUNTRIES
FEDERAL REGION II
GEOLOGIC AGES
GEOLOGY
MESOZOIC ERA
NORTH AMERICA
USA
580000* - Geosciences