Which of the following are evidence for an asteroid impact being the cause of the extinction of the dinosaurs 65 million years ago (as well as 75% of all species alive at the time)?
A)a worldwide layer of the element iridium in 65 million year old rocks
B)no dinosaur fossils being present in rocks younger than 65 million years old
C)a buried crater more than 100 km across in the Gulf of Mexico
D)all of the above

Question

Quizplus · Accepted Answer

All of these options are evidence for an asteroid impact being the cause of the extinction of the dinosaurs. The layer of iridium is consistent with an asteroid impact, the lack of dinosaur fossils in younger rocks suggests a sudden extinction event, and the buried crater in the Gulf of Mexico is the direct evidence of an impact.

Which of the Following Are Evidence for an Asteroid Impact