In 1958, Australian geophysicist Warren Carey postulated that the reason the coastlines matched so well across the Atlantic was because they had moved apart as the Earth expanded. The young ages initially measured for the ocean floor added some weight to this idea, but again no satisfactory mechanism could be found. The rigidity of the continents and their lack of deformation despite the change in curvature, and the implied change in the density of the Earth’s interior were also problems.

IMAGE REFERENCE: Samuel Warren Carey’s fit of Africa & South America, from Carey, S W, “Wegener’s South America-Africa assembly, fit or misfit?”, Geological Magazine, 92(3): 196-200 (1955)