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Extinction of the Extinction of the DinosaursDinosaursBy Chris KeachBy Chris Keach
The KT-Extinction eventThe KT-Extinction event
The KT extinction event The KT extinction event was a massive was a massive extinction of several extinction of several species at the end of the species at the end of the Cretaceous period. It is Cretaceous period. It is called the KT-Extinction called the KT-Extinction event because it marks event because it marks the transitioning of the the transitioning of the cretaceous period into cretaceous period into the tertiary period. the tertiary period. Which occurred about Which occurred about 6.5 million years ago. 6.5 million years ago. This period is marked by This period is marked by a geological marker a geological marker known as the KT known as the KT boundaryboundary
Theories on extinctionTheories on extinction
He believes that there is an unusually high concentration of iridium in the KT boundary. Iridium is generally rare in the earths surface, but common in asteroids and meteors.
Physicist Luis Alvarez suggested that a large meteor impact may be responsible for wiping out the dinosaurs.
The problem with Alvarez’s theory is that there is no impact crater from a large enough meteor to cause the amount of dust and change in weather that would have been necessary for a worldwide extinction which leads to the idea of a multiple impact.
The Silverpit And Boltysh craters pictured above, as well as the Eagle Butte, and Vista alegre craters in canada and brazil are all dated about 65 million years old. If they all struck within a few years of each other, they would have easily been responsible for the KT extinction event
Multiple Impact theory
Deccan Traps TheoryDeccan Traps Theory
Another theory is that high volcanic activity caused the KT Extincton event. A series of volcanoes in india known as the Deccan traps may have caused or contributed to the extinction
Volcanoes on the VEI-8 (volcanic explosive index) range can easily cover the earth in enough dust and smog to cause a volcanic winter and ice age, so a volcanic eruption could have easily contributed to the dinosaurs extinction
Mass Extinction
While we are not sure exactly what happened, what we do know is that one or many events occurred within a period of time that drastically altered the climate of the earth. Whether a meteor impact, volcanic eruptions, or a multitude of reasons, the dinosaur population could not cope with the environment change brought about.