Chunk Loading/Freezing Issue

Only happening with one world in particular. Whenever I try to load in the world, it only loads chunks up to a certain X-value plane, and then drops off into nothing. If you try to approach the drop-off, the world freezes and the game later crashes. In addition, the chunk-loading square in the loading screen for the world doesn't completely fill before entering the world. This only started happening recently and only with this one world.