Multiple Choice
The iridium layer at the Cretaceous-Tertiary boundary is attributed to
A) meteorite bombardment.
B) massive volcanic eruptions.
C) massive earthquakes and shock waves.
D) extinction of the dinosaurs.
Correct Answer:
Verified
Correct Answer:
Verified
Q28: During the Pleistocene ice age<br>A)there was one
Q29: The first time period for which abundant
Q30: The time required for one-half of a
Q31: The Permian extinction predominantly affected<br>A)reptiles.<br>B)marine life.<br>C)insects life.<br>D)terrestrial
Q32: During the Mesozoic,the supercontinent of Laurasia fragmented
Q34: Radiometric dating assumes that,once a mineral has
Q35: During the Mesozoic,the supercontinent of Gondwanaland fragmented
Q36: Radiometric dating is based on<br>A)decay of uranium-238
Q37: Life forms in the Precambrian included<br>A)trilobites.<br>B)brachiopods.<br>C)coelacanths.<br>D)cyanobacteria.
Q38: Granitic pebbles with a radiometric age of