ha ha! the kt mass extinction boundary. kt (cretaceous tertiary) boundary layer exists...

Post on 14-Dec-2015

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Ha Ha!

The KT mass extinction boundary

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 500,000sqkm

• 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

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