How could a geologic map provide evidence of new plate growth?

As they show where rock exposed at the surface, structural features such as faults, folds, foliations, and lineations are shown with strike and dip or trend and plunge symbols which give these features' three-dimensional orientations. As new plates grow, the rock features will change, by comparing older and current geologic maps, one can compare to see if new plate growth has occurred. 

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