I was exploring a new world to test & observe performance and such and encountered this odd generation of a badlands mineshaft. From what I've seen, they're normally supposed to only spawn in caves and mountains, although this may be a feature I missed in the lengthy patch notes. Either way, it's an interesting discovery nonetheless. (Note: this might be a one-chunk glitch since I couldn't find it anywhere else in the world.) I also found some other possible world generation bugs that I'll report later.
Coords (X,Y,Z): -1286 ~ 1439
Thanks, and have a wonderful day.