Impact Theory of Mass Extinctions and the Invertebrate Fossil Record

  title={Impact Theory of Mass Extinctions and the Invertebrate Fossil Record},
  author={Walter Alvarez and Erle G. Kauffman and Finn Surlyk and Luis W. Alvarez and Frank. Asaro and Helen V. Michel},
  pages={1135 - 1141}
There is much evidence that the Cretaceous-Tertiary boundary was marked by a massive meteorite impact. Theoretical consideration of the consquences of such an impact predicts sharp extinctions in many groups of animals precisely at the boundary. Paleontological data clearly show gradual declines in diversity over the last 1 to 10 million years in various invertebrate groups.Reexamination of data from careful studies of the best sections shows that, in addition to undergoing the decline, four… 
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Molluscan extinction patterns across the Cenomanian-Turonian stage boundary in the western interior of the United States
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The Eocene-Oligocene boundary is widely cited as the "other" example (besides the Cretaceous-Tertiary boundary) of a known relationship between mass extinctions and bolide impacts. The stratigraphic
Sedimentology and Extinction Patterns Across the Cretaceous-Tertiary Boundary Interval in East Texas
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Taxonomic selectivity and continuous variation in mass and background extinctions of marine taxa
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Effects of stratigraphic completeness on interpretations of extinction rates across the Cretaceous-Tertiary boundary
A rate of extinction must specify both the amount of taxonomic change and the duration of that change. A consistent means of temporal measurement must be used to establish the duration. Terms used to


Terminal Cretaceous Events
SEVERAL explanations have been offered (see refs. 1–3) for the abrupt faunal extinctions at the end of the Cretaceous and, with the advent of the JOIDES Deep Sea Drilling Project, it was hoped that
Sudden death at the end of Mesozoic
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Land plant evidence compatible with gradual, not catastrophic, change at the end of the Cretaceous
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The hypothesis that a catastrophic impact of an extraterrestrial body caused the terminal Cretaceous mass extinctions of dinosaurs, planktonic foraminfera and other species is now accepted as
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The major extinction of life on the earth at the end of the Cretaceous Period may be related to the meteorite impact, as the enriched noble metals in the clay are present in cosmic proportions, indicating that the impacting celestial body had not undergone gross chemical differentiation.
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A model of the evolution and radiative effects of a debris cloud from a hypothesized impact event at the Cretaceous-Tertiary boundary suggests that the cloud could have reduced the amount of light at
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