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The KT mass extinction boundary. Ha Ha!. KT (Cretaceous Tertiary) Boundary. Layer exists simultaneously world wide Layer marks the transition from the Mesozoic era to the Cenozoic Layer Marks the transition from the Cretaceous to the Tertiary
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KT (Cretaceous Tertiary) Boundary • Layer exists simultaneously world wide • Layer marks the transition from the Mesozoic era to the Cenozoic • Layer Marks the transition from the Cretaceous to the Tertiary • Layer had 30-130 times the normal amount of the element Iridium
Devastation Sequence • Asteroid impacts Earth • Ejecta is sent into atmosphere • Material blocks sunlight for months to years • Impact crater and fallout layer are the only evidence
Chicxulub • The crater is buried under the tip of the Yucatan peninsula • Crater is 110 miles wide • Crater is 65.5 millions years old • Crater is named after the Mayan word for (Tail of the Devil)
Other Theories • Deccan Traps • Sea level Regression • Multiple impacts • Multiple events
Deccan Traps • South West India • Area 500,000sqkm • 2000m thick • May have lasted 30,000 years
Maastrichtian sea-level regression • Reduction of continental shelf area • Reefs and Plankton my have been seriously damaged • Epeiric seas would have disappeared
Multiple Events • Extinction was gradual and involved the loss of species and genera. • Dinosaurs, air and marine reptiles were picked off by a combination of all these sequential events.
State of the art re-creation • http://www.youtube.com/watch?v=p0aHXSmCstk