On: NASA Maps Surface Changes from California Quakes

[antoineMoPa]

If I understand the right thing, from one red "line" to another, there has been a 4.8 inch displacement between the two photos.

[cardiffspaceman → antoineMoPa]

Since the description says each color cycle represents 4.8 inches, I would say if you trace a line from one red pixel across the blue pixels to another red pixel, you've traversed a cycle, and you've increased or decreased displacement from the reference by 4.8 inches.