Certain metallic crystals leave a record of the polarity of the earth at the point in time when they were formed in molten rock because they:
A)leave radioactive "signatures" that scientists can read
B)act as small magnets that orient themselves to the poles before the rock solidifies
C)form ring-type patterns like tree rings that can be counted
D)contain amino acids which form as crystals,and this change in the amino acids can be used to determine the passage of time

Question

Quizplus · Accepted Answer

Metallic crystals act as small magnets that align themselves with the polarity of the Earth at the time of formation. This alignment is preserved when the rock solidifies, creating a record of the Earth's polarity at that point in time.

Certain Metallic Crystals Leave a Record of the Polarity of the Earth