Volcanoes often will be sheered in half, where only a portion of the volcano gets generated and results is a huge exposed surface.

I'm not going to give up on finding this again so I can get a good screenshot. I've crossed paths with a few of them. It only seems to happen on ocean-locked volcanoes. Those connected to other non-ocean biomes don't seem to have the issue.

Hopefully, I'll be able to find one soon.

The major issue is when they are cut vertically, and it becomes ocean biome. Attempting to find a screenshot.

You need to keep in mind, our volcanos are biomes in themselves. They are not giant anthill-like world gen features. I'd have to see a screenshot of them being 'cut vertically' to make a proper judgement on whether or not it is an issue.

I think I have it figured out. It occurs when the Deep Ocean biome is adjacent to an ocean sub-biome.
I have a screenshot of the mangrove biome that is doing the same thing. I can only assume mangrove is a subbiome.

Perhaps the min/max elevations are just not flowing well between Deep Ocean and the subbiomes

Also next to a deep ocean.

Could i please get a seed/coords to test these with? It does indeed appear to be a bug by the looks of things

I'm pleased someone else was able to see the issue. Great screenshot, BBoldt.

Seed: -3802979829429193980

Hrm, I had no problems with the above seed and coords @EchoingZen. I'd presume you are using the latest BoP for 1.7? (Either the 2.0.0 RB or the 2.0.1 RB as generation should have gone unchanged between the two)

I'll get another one with just BoP 2.0.1.890 and OptiFine (Shouldn't mess with WorldGen).
I'm not exactly sure why that other one didn't work. I deleted my configs, maybe something was left in there. One more screenshot coming up.