The high concentration of iridium at the Cretaceous Tertiary boundary is most likely attributed to
A)a worldwide rise in sea level.
B)meteorite bombardment.
C)an out flux of iridium from Earth's interior.
D)none of the above

Question

Quizplus · Accepted Answer

The high concentration of iridium at the Cretaceous Tertiary boundary is believed to be attributed to a meteorite impact. Iridium is a rare element on Earth's crust, but it is more common in meteorites. Therefore, the sudden influx of iridium at the boundary suggests a large meteorite impact, which is also supported by the existence of the Chicxulub Crater in Mexico. The other options are not supported by scientific evidence.

The High Concentration of Iridium at the Cretaceous Tertiary Boundary