When creating a customized world I discovered a problem with the Biome Depth Weight setting. When setting it higher than the default odd spikes begin showing up, primarily along or in ocean and beach biomes.They range from short narrow spikes to tall square-shaped pillars.

After some testing the threshold seems to be around a setting of 1.125. I also found that the phenomenon happens along rivers as well when the setting is put to 4 or higher.

The preset I first encountered this with is included. The bug happears across multiple presets and seeds however and seems unaffected by the other settings.