What evidence supports the Cretaceous extinction?
Some evidence supporting the impact is the dent and rings that circle the crater which are found submerged underneath the water in the Gulf of Mexico. More supporting evidence is in the form of elevated iridium levels and shocked quarts.
What evidence is there for the extinction of dinosaurs?
Evidence suggests an asteroid impact was the main culprit. Volcanic eruptions that caused large-scale climate change may also have been involved, together with more gradual changes to Earth’s climate that happened over millions of years.
What is the evidence for an impact event at the end Cretaceous and how could this have caused a global mass extinction?
As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was caused by the impact of a massive comet or asteroid 10 to 15 km (6 to 9 mi) wide, 66 million years ago, which devastated the global environment, mainly through a …
What evidence in the fossil record supports the explanation that volcanic activity caused the Cretaceous extinction?
Lava flows like these provide evidence of a rash of volcanic activity for at least 500,000 years leading up to the extinction of the dinosaurs. The metal iridium, which is similar to platinum, is very rare on Earth’s surface but is more common in asteroids and in molten rock deep within the planet.
What was the cause and what evidence exists of the KT mass extinction event?
The Cretaceous-Tertiary extinction event, or the K-T event, is the name given to the die-off of the dinosaurs and other species that took place some 65.5 million years ago. For many years, paleontologists believed this event was caused by climate and geological changes that interrupted the dinosaurs’ food supply.
What are the evidence of volcanic eruption?
Notable precursors to an eruption might include: An increase in the frequency and intensity of felt earthquakes. Noticeable steaming or fumarolic activity and new or enlarged areas of hot ground. Subtle swelling of the ground surface. Small changes in heat flow.
What piece of evidence initially convinced Dr Alvarez that a mass extinction has occured at the KT boundary?
What piece of evidence initially convinced Dr. Alvarez that a mass extinction had occurred at the K-T boundary? There were many different foram fossils below the boundary between the Cretaceous and Tertiary periods and fewer above the boundary, which means that the boundary marks the time of the mass extinction.
What piece of evidence initially convinced Dr Alvarez that a mass extinction had occurred at the KT boundary quizlet?
The first clue that an asteroid had struck earth at around the same time as the mass extinction was the amount of iridium around the K-T boundary.
What evidence is there to support the asteroid collision theory?
The asteroid impact theory is supported by quite a bit of evidence. For example, the fossil record shows that dinosaurs went extinct very suddenly. This is more consistent with a major disaster like an asteroid impact than it is with a gradual change in climate or volcanic activity.