Strange mini aquifer wall-like structures can generate on the surface very commonly, creating a very scattered chaotic look. They aren't really hard to find either, simply flying around a world in 21w37a will show many such examples especially in plains and deserts.
I think they're either happening because of the way aquifer walls generate, creating walls around water that isn't there or is below the surface, or maybe because of noodle caves?
Steps to Reproduce:
- Enter the following seed and coordinates.
Notice how strange mini broken aquifer walls commonly generate on the surface.
Tiny curvy broken cave/wall-like structures to not be generating on the surface. These should only generate around entire aquifers. It doesn't look intended.