The polarity of the Earth's magnetic field in the geologic past is
A) unknown,but is assumed to have been identical to today's.
B) known to have stayed constant through geologic time,as shown by remnant magnetization of iron-rich minerals in rocks.
C) known to have experienced numerous reversals,as shown by remnant magnetization of iron-rich minerals in rocks.
D) known to have stayed constant through time,based on theoretical calculations.

Question

Quizplus · Accepted Answer

The remnant magnetization of iron-rich minerals in rocks have provided evidence that the polarity of the Earth's magnetic field has experienced numerous reversals in the geologic past. Therefore, option C is the correct answer. The other options are incorrect as they do not reflect the current understanding of the Earth's magnetic field.

The Polarity of the Earth's Magnetic Field in the Geologic