By radiometric dating, the oldest mineral in a sedimentary rock was found to be 1.4 million years old. What is the age of the sedimentary rock?
A)Radiometric dating does not work for sedimentary rocks.
B)1.4 million years.
C)No older than 1.4 million years.
D)No younger than 1.4 million years.

Question

Quizplus · Accepted Answer

Sedimentary rocks are composed of materials from pre-existing rocks, so the age of the sedimentary rock cannot be older than the oldest mineral it contains.

By Radiometric Dating, the Oldest Mineral in a Sedimentary Rock