|
65 million years ago a mass extinction event ended the age of dinosaurs. The end of the Cretaceous period is marked over much of the Earth by a discontinuity with high Iridium levels and an abrupt change in flora and fauna. Aproximately 50% of all genera went extinct during this event. There are a number of theories as to what caused this event, detailed below. |
|
65 million years ago a mass extinction event ended the age of dinosaurs. The end of the Cretaceous period is marked over much of the Earth by a discontinuity with high Iridium levels and an abrupt change in flora and fauna. Approximately 50% of all genera went extinct during this event. There are a number of theories as to what caused this event, detailed below. |
|
[LW Alverez]? first discovered the high Iridium levels at the Cretaceous-Tertiary (KT) boundry in 1980. He hypothesized that an asteriod hitting the earth was responsible. Iridium is very rare on the Earth's surface, but much more common in the Earth's interior as well as in extraterrestrial objects, such as asteriods and comets. The discovery of a crater burried under Chicxulub in the Yucatan as well as varios types of debris in North America have lended credibility to this theory. Most paleontologists? agree that an asteroid did hit the Earth 65 million years ago, there is still disagreement over whether that impact caused the extinction. |
|
[LW Alverez]? first discovered the high Iridium levels at the Cretaceous-Tertiary (KT) boundry in 1980. He hypothesized that an asteriod hitting the earth was responsible. Iridium is very rare on the Earth's surface, but much more common in the Earth's interior as well as in extraterrestrial objects, such as asteriods and comets. The discovery of a crater burried under Chicxulub in the Yucatan as well as varios types of debris in North America have lended credibility to this theory. Most paleontologists? agree that an asteroid did hit the Earth 65 million years ago, there is still disagreement over whether that impact caused the extinction. |
![[Home]](wikipedia.png)