Marine geologists can predict the age of igneous rocks of the sea floor by measuring _____.
A) the percent of iron-rich minerals in the rock
B) their grain size
C) the velocity of earthquake waves
D) their density
E) magnetic anomalies

Question

Quizplus · Accepted Answer

Marine geologists can predict the age of the sea floor rocks by measuring magnetic anomalies, which are strips or bands of different magnetic polarity on the ocean floor. As the Earth's magnetic field reverses over time, the newly formed rocks record the polarity of the magnetic field at the time of their formation, and these changes can be detected and used to assign an age to the rocks.

Marine Geologists Can Predict the Age of Igneous Rocks of the Sea