I was flying across an ocean in creative mode using the Feed the Beast modpack when I found some very strange and glitch-esque terrain generation. It occurred precisely on a vertical (north to south) chunk boundary. Random grass block patches would be generated at sea level and would continue downwards to the sea floor. From diving into to water between the dirt pillars, I could see that all the blocks are generated as grass blocks. The water between the pillars is flowing and the lag is so bad that I can't do anything. I'm not certain what is causing the lag. Also, I'm not sure whether or not this is being caused by a Feed the Beast mod. The debug info says that the biome is ocean, so I don't think it's a biome from the modpack. I'd like to get some feedback on this as I'm very curious. Below is a screenshot which includes a minimap that shows the surrounding terrain and my coordinates. The coordinates are, in case it's hard to see, (x: 2524, y: 63, z: -6419) Thanks.
Zombiecraft Maps!