Exam 24: Geologic Time

Sedimentary layer A lies above sedimentary layer B,and both are cut by an igneous dike,C.Therefore,the order from oldest to youngest is

Rubidium-______________ dating is an important radiometric dating tool.

The first 87% of geologic time is often called

Atomic nuclei that decay of their own accord are said to be ______________.

The hollow depression left when a shell or bone is dissolved completely out of a rock is called a(n)

We live in the ______________ epoch.

The Jurassic is a(n)

Lack of knowledge of the phenomenon called ______________ led Lord Kelvin to an incorrect estimate of the age of Earth.