The KT mass extinction boundary Ha Ha KT
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 • Layer had 30 -130 times the normal amount of the element Iridium
Alvarez impact hypothesis
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
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)
Chicxulub Gravity Anomaly
Other Theories • • Deccan Traps Sea level Regression Multiple impacts Multiple events
The Deccan traps
Deccan Traps • • South West India Area 500, 000 sqkm 2000 m 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=p 0 a. HXS m. Cstk
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