![Geography Notes for UPSC](https://www.gkseries.com/blog/wp-content/uploads/2021/10/Copy-of-Geography-Class-Made-with-PosterMyWall.jpg)
The strips of normal and reverse magnetic field that parallel the mid-oceanic ridges help scientists determine the rates of plate movement.
The Arctic Ridge has the slowest rate (less than 2.5 cm/yr), and the East Pacific Rise near Easter Island, in the South Pacific about 3,400 km west of Chile, has the fastest rate (more than 15 cm/yr).