@article{80,
  author = {Gerta Keller},
  title = {The end-Cretaceous mass extinction in the marine realm: year 2000 assessment},
  abstract = {<p>The current database indicates that the terminal decline and extinction, or near extinction, of many groups commonly attributed to an asteroid or comet impact at the Cretaceous{\textendash}Tertiary (K{\textendash}T) boundary (e.g., ammonites, bivalves, planktic foraminifera) began during the last 500 k:y: of the Maastrichtian. By the time of the K{\textendash}T boundary, extinction-prone tropical and subtropical marine faunas and 4oras were almost gone, or had severely reduced species populations struggling to survive. The K{\textendash}T boundary kill-e5ect was largely restricted to these struggling tropical and subtropical populations that accounted for 2=3 of the species among planktic foraminifera, but less than 10\% of the total foraminiferal population. No signi7cant extinctions occurred among ecological generalists that dominated across latitudes. No single kill mechanism can account for this mass extinction pattern. The last 500 k:y: of the Maastrichtian were characterized by a series of rapid and extreme climate changes characterized by 3{\textendash}4{\textopenbullet}C warming between 65.4 and 65:2 Ma, major volcanic activity between 65.4 and 65:2 Ma, a spherule-producing event between 65.3 and 65:2 Ma, and an impact at the K{\textendash}T boundary (65:0 Ma). All of these events caused major environmental perturbations and biotic stresses that resulted in severe reductions in species populations and extinctions that culminated at the K{\textendash}T boundary. The mass extinction pattern, and the parallel environmental changes during the last 500 k:y: of the Maastrichtian, suggest that both long-term (climate, sea-level) and short-term (impact, volcanism) events contributed to the K{\textendash}T boundary mass extinction. \&nbsp; <a href="https://geoweb.princeton.edu/research/keller/pubs/Keller_2001_year_2000_ass.pdf" target="_blank">PDF</a></p>
},
  year = {2001},
  journal = {Planetary and Space Science},
  volume = {49},
  pages = {817 - 830},
  month = {Jan-07-2001},
  issn = {00320633},
  url = {http://linkinghub.elsevier.com/retrieve/pii/S0032063301000320},
  doi = {10.1016/S0032-0633(01)00032-0},
  language = {eng},
}