The issue is for treasure maps.  In my search for the heart of the sea, I have gotten at least 25 treasure maps from shipwrecks and ruins.  These maps have been found over a span of 20000 blocks in two directions.  However, they all point towards one location, one that I have already looted.  I destroyed the chest AND the entire island, but the maps all point towards the same place.

I have tried to open the maps thousands of blocks away, but they still pointed towards the same location.  Apparently, this bug is common, so I just wanted to add my story too.