We know that the outer crust of the Earth is broken up into pieces (plates) and these plates emerge from certain lines (e.g. the Mid-Atlantic Ridge) and also fall back into the Mantle in other lines such as subduction zones (near Chile, for example).
The main conversation about this generally involves how the continents have moved around but my question is not about that. My question is: How have the boundary lines where plates emerge and sink back changed in location relative to each other over the history of the Earth? There are no reference points on the surface of the Earth's crust involved here, i'm only interested in the locations of where the boundaries are relative to each other.