Editing Fracture zone (section)

==Geologic importance==
[[Image:Blanco Fracture Zone.jpg|thumb|upright=1.35|Blanco fracture zone map]]
[[Image:Charlie-gibbs-full-extent.png|thumb|upright=1.35|[[Bathymetry]] map of the North Atlantic Ocean showing the full extent of the Charlie-Gibbs fracture zone (horizontal black lines in the center of the image)]]
[[File:BetweenErebusAndUdintsevFZs.png|thumb|upright=1.35|[[Magnetostratigraphy]] of the East Pacific Rise near the [[Heirtzler fracture zone]] showing ages of sea floor spreading in millions of years (Ma)]]
[[Image:Romanche Trench.jpg|thumb|upright=1.35|The Romanche fracture zone with red arrows indicating directions of movements of tectonic plates]]
As many areas of the ocean floor, particularly the Atlantic Ocean, are currently inactive, it can be difficult to find past plate motion. However, by observing the fracture zones, one can determine both the direction and rate of past plate motion. This is found by observing the patterns of magnetic striping on the ocean floor (a result of the reversals of Earth's magnetic field over time). By measuring the offset in the magnetic striping, one can then determine the rate of past plate motions.<ref>{{cite web|title=Understanding Plate Motions|url=https://pubs.usgs.gov/gip/dynamic/understanding.html|publisher=United States Geological Survey}}</ref> In a similar method, one can use the relative ages of the seafloor on either side of a fracture zone to determine the rate of past plate motions. By comparing how offset similarly aged seafloor is, one can determine how quickly the plate has moved.<ref name="Columbia" />