After a game load I noticed a chunk out of place. After a quick search I noticed several others. They seem to be cloned from existing chunks as I found part of my sugarcane farm on one of these glitched chunks. They only seem to be near my spawn chunks. Thankfully they have not spawned on any of my structures, however they do intersect the land in places that have been cleared by me. Tried exiting Minecraft and reentering world. Problem persists, it appears to have been saved to my world.