A core sample is taken 100 km west of and parallel to a ridge system. Magnetic readings of the rock show a reversal of the Earth's magnetic field. How many km east of the ridge system must scientists travel to collect a core sample with the same magnetic properties?
A) 50
B) 100
C) 200
D) 0 km; collect the sample directly at the ridge

Question

Quizplus · Accepted Answer

The Earth's magnetic field reversals are symmetric about mid-ocean ridges due to seafloor spreading. If a core sample 100 km west shows a reversal, a core sample 100 km east will have formed at the same time and exhibit the same magnetic properties.

A Core Sample Is Taken 100 Km West of and Parallel